It is now a commonplace that the centrifugal devolution of governmental authority which characterised the development of the feudal nobility in Europe was arrested in England by the impact of the Norman invasion, and by the strength and authority of the early Norman and Angevin kings. Thus, whilst the general structure of the Anglo Norman nobility followed the overall pattern of continental Europe, that nobility was itself profoundly influenced by new and unique factors which arose from the conditions of the Conquest.
It is often argued, for example, that the Conquest caused a major break in the continuity of English history, and so far as the Anglo Saxon nobility was concerned the break proved to be more or less permanent. It is less often said that the Conquest brought about a comparable hiatus in the development of the invading Norman nobility, transforming it in a relatively short time into an Anglo Norman nobility differing significantly in structure and character from its Norman and European counterparts. The Conquest, then deflected the course of English history as a whole.
The Conquest, in theory at least, also brought about the feudalisation of England, but, again, Anglo-Norman feudalism differed sharply from the Continental variety. It differed also because it was ostensibly 'imposed' over a relatively short period of time, instead of emerging from the Carolingian undergrowth as a hierarchy of usurped immunities whose survival depended on the maintenance of a successful balance between the exclusion of superior authorities and the duties of feudal allegiance. Lastly, the Norman kings of England inherited from their Anglo-Saxon predecessors various rights and powers which were very different in character from those exercised by purely feudal monarchs. The very fact of the Conquest, then, sowed the seed of rapid change in Anglo-Norman society, and no group amongst the Normans changed more rapidly than the ubiquitous knights.
For about a generation after the Conquest the Norman knight remained an unexceptional, and generally unenfeoffed, warrior, permanently maintained in royal and baronial households, until such time as the Norman settlement was considered secure. The period in which enfeoffment and subinfeudation began is obscure. D.C. Douglas suggests l086 as the end of the first period of English feudalis, but Professor Miller has shown that the knightly tenants on the estates of the Abbot of Ely were themselves subinfeudating fees by l086. It seems likely that the feudal settlement did not achieve its initial and transitory stability until the death of Henry I, by which time the tenurial organisation of the realm appears to have been fully implemented and the military obligations of knightly mesne tenants more closely defined. At all events enfeoffed knights appear to have been relatively rare before the last quarter of the eleventh century, and it is very possible that the enfeoffments of the l080's represents the practical superannuation of the generation of knights who took part in the Conquest and maintained the Norman presence in the years immediately after it. If it is assumed that the active military life of a knight was between l0 - l2 years, and the possible life expectancy around 50 - 60 years, a knight who was in his prime at the time of the conquest, that is to say between the ages of l8 and 30, would probably expect to be rewarded with a fief at around the age of 40, that is to say, in the l080s. The actuarial aspects of enfeoffment have attracted little attention from historians, but fees may equally be regarded as rewards for services already performed, as well as guaranteeing services to be performed in the future.However, even when knights had been enfeoffed there is no reason to believe that their military obligations were immediately forgotten, or that the knights themselves soon settled into lives of decent rustic obscurity. E.J. King's analysis of the Peterborough 'Descriptio Militum' of about 1100-1166, demonstrates very clearly the primarily military character of the early fiefs and of their tenants, as does the eleventh clause of Henry I's coronation charter, which exempted the knights from geld on demesne ploughs so that 'they may better provide themselves with horses and arms'. The fact that they had ploughs at all prepared the way for future developments. The fiefs of the Earls of Chester were still fully organised for war as late as l2l5, although it was a sign of the times that knight service was to be enjoined on all holders of fees, whether knights or not. There can be little doubt, therefore, that the first wave of enfeoffments was no mere pensioning off of retiring 'milites'; those who received fiefs were intended to fulfil their military obligations. Whether or not they were able to do so is another matter.
Nevertheless enfeoffment necessarily changed the character of the Norman knights. They ceased, by definition, to be full-time professional soldiers, and, at the same time, they acquired the landed resources and minor rights of jurisdiction through which they might hope to transform themselves into a genuine lesser nobility. Initially the fiefs granted to mesne tenants were not hereditary, but customary tendencies operated in that direction, and allowed knightly families to consolidate their hold on the land. As this hold was transmitted over several generations three major problems emerged which in turn profoundly influenced the long term development of both the gentry and the monarchy. Each of these problems may now be considered in turn.
Firstly, alienation and subinfeudation of fiefs by mesne tenants soon created serious legal problems which could not be resolved within the existing framework of customary and feudal law. The legal repercussions of subinfeudation were necessarily delayed for at least two generations between the death of William I and the accession of Henry II. During this period families of mesne tenants had ample time to subdivide their holdings, either within or without their own families, and to create a multitude of problems relating to their rights of seisin. Many of these problems could not be solved by the normal legal relations between a feudal subtenant and his lord, especially where the lordship was itself divided. Subinfeudation undoubtedly grieved and aggravated superior lords, and exposed new subtenants to the feudal expedients of distraint and disseisin for default of services due. Allowing that some 50 to 60 years would suffice for complications of this kind to emerge, the reign of Henry II could be postulated as a likely time for some revision of the land law to cover new contingencies. In fact royal cognizance of possessory actions had already begun, in a hesitant way, during the reign of Stephen, to rebuff attempts by the church courts to claim jurisdiction over lay Fees held of churches. The same reign is more notable, however, for the attempts of certain lords to solve their tenurial disputes by main force, and the anarchy helped to create an atmosphere in which future legal intervention by the crown would be welcomed, especially by the knightly and mesne tenants who were the chief victims of baronial depredation.
Legal innovation, therefore, followed logically upon the failure of the ostensibly simple, but inflexible, system of feudal law to cover a variety of basically non-feudal legal contingencies. The provision of legal remedies, moreover, allowed the monarchy to expand its legal authority outside the formal hierarchy of the feudal courts whilst at the same time bringing the mesne tenants into direct relationship with the crown, as suitors, litigants, and officials in the royal courts. As a corollary, royal protection of seisin entrenched the mesne tenants evermore firmly on their land, so that the precarious element in tenure by knight service was progressively removed. The legal innovations of Henry II thus endowed the feudal tenant with something approaching real ownership of his lands, including freedom of alienation. At this point the lands constituting a knight's fee or fees also became genuinely heritable, as the lordship of the lands passed by right to the heirs who were constrained only by the obligation to pay a relief for the continuance of a seisin which could no longer be withheld. This transformation of nominal life tenancies, customarily regranted to the tenants heirs, into a legally defended right of inheritance further weakened the already loose bond between lords and tenants. For the future the advantage appeared to lie with the tenant.
Secondly, the progressive collapse of the feudal arrangements as a stable system of land tenure had obvious and immediate repercussions on the operation of the feudal military system, though it is evident that the Norman and Angevin kings never relied exclusively on purely feudal resources. The Normans were quick to adapt the Anglo Saxon fyrd to their own uses, and successive kings after Henry I made increasing use of mercenaries, led by a corps d'elite of feudal cavalry. The considerable and growing wealth of eleventh and twelfth century England enabled the Norman and Angevin kings both to hire mercenaries, and to secure quasi-feudal services by the concession of fiefs-rentes, which could be used especially to maintain diplomatic or political arrangements within their continental dominions. From the reign of Henry I, if not earlier, the English army included a significant proportion of non-feudal levies. 
This increasing use of mercenaries may be accounted for by two further factors. Firstly, the enfeoffment of knights maintained in baronial households effectively reduced the number of knights available for immediate mobilisation. More important, enfeoffment limited the terms of service to between 40 and 60 days in each year. The effectiveness of a purely feudal force was thus severely limited by the extremely short period in which it could be made to operate. Moreover, the rapid ruralization of the knights, and their subsequent subinfeudation of their estates, compromised the extent to which even this limited service could be exacted. The practical defection of the lower ranks of the feudal hierarchy thus forced the king to adopt alternative or supplementary military arrangement. The need to adopt these measures depended, of course, on the immediate military needs of the crown, and these were conditioned in turn by foreign and domestic politics.
The second motive for securing a mercenary army to supplement the feudal host was thus supplied by the increasing strength and aggressiveness of the Capetian monarchy, which necessitated the maintenance of a permanent English military force on the continent. However the great expansion of the Angevin empire raised in an acute form the problem of feudal service abroad, for it was by no means clearly established that English feudal tenants owed military service outside England. The extent of the empire also emphasised the tactical disadvantage of a purely feudal force. The dispersion of enfeoffed vassals delayed the constitution of the host, and the limited and often irregular terms of service prevented a satisfactory or conclusive prosecution of extended military campaigns. Changes in strategy, particularly the development of castles and siege warfare reduced the practical value of an expensive cavalry force and accelerated the commutation of corporal feudal obligations to cash payments in lieu of service. At the same time the status of those who did serve in the reduced feudal quota was enhanced to the rank of professional officers. Modifications and progressive reductions of the servitia debita during the second half of the twelfth century further emphasised the professional aspect of 'feudal' service and started the simple fighting knight on the hard and expensive road to the glittering baronial chivalry of the fourteenth century.
It may be speculated that the transition from corporal to commuted service was also in part a consequence of the hiatus between the enfeoffment of the first generation of household knights in the l080's, and the majority of a new generation of knights old enough to do the service due from their father's fiefs. If the household knights were between 30 and 40 at the date of enfeoffment, and also unmarried, adequate military service would not be available for another l8 to 20 years. In the interim commutation would be inevitable.
The use of mercenaries up to the reign of Henry II thus introduced important changes in the nature of both the crown and the knights. The crown was obliged to extend its fiscal authority in order to administer the revenues derived from commuted obligations, and, in so doing, set up the foundations of a fiscal bureaucracy which very soon held all tenants in chief to account. On the other hand, the fiscal exploitation of feudal obligations had the paradoxical effect of rigidifying the formal aspects of feudal service, whilst at the same time allowing the knights to become defeudalised in any practical sense. By permitting cash commutation for military obligations the crown condoned and consolidated the ruralization of the knights and initiated their transformation into a country gentry.
Both of these processes, initiated in the l080s by the settlement of the knights on the land, were well advanced by the reign of Henry II. Henry himself, whilst actively encouraging the military and chivalrous aspects of knighthood, recognised the growing distinction between the rural and the professional knight. Robert de Torigny, writing in 1159, demonstrates the problems with which Henry was faced and shows how his solution of them was made in the context of a society in which military services was no longer the only characteristic of knighthood:
Rex igitur Henricus in expeditionem praedictam, et considerans longitudinem
et difficultatem viae, nolens vexare agrarios milites, nec burgensium,
nec rusticorum multitudinem, sumptis ix solidis Andegavensium in Normannia
de feudo unius eijusque loricae etc. 
and in ll70 Giraldus Cambrensis describes the rustic knight industriously caring for his crops. 
These problems were by no means new; slightly more than sixty years earlier Archbishop Anselm was reprimanded by Rufus for sending knights to the Welsh campaign who were neither properly equipped, nor properly instructed.  It might be added in mitigation that these unfortunates were the descendants of Anglo-Saxon 'drengs' unwisely converted to knights by Anselm's predecessor. Henry's leniency towards the rustic knights did notlast. By 118l he was obliged to impose strict regulations on the armour appropriate to all holding a knight's fee, or fees. The shirt of mail, helmet, shield and lance stipulated in the Assize of Arms contrast sharply with the simple Hauberk mentioned in the second clause of Henry I's coronation charter. The rising cost and complexity of knightly equipment now began to impose a new and economic criterion of military knighthood which progressively excluded the poorer rustic knights.
The third and last major effect of the enfeoffment of the knights was the separation of the emerging gentry from their baronial overlords. This separation was both military and political, in an age when armed might and political influence were almost synonymous, and it followed inevitably from the ruralization of the knights. Recalcitrant mesne vassals were not unknown, even in the reign of Henry I. By the end of the twelfthcentury many of the greater tenants in chief were increasingly unable to exact service from vassals beyond the terms of their enfeoffment, whilst other military tenants were unwilling to provide themselves with the proper equipment.  By enforcing liege homage on all feudal tenants Henry II further detached the knights from the political control of their feudal overlords. Thus the barons who rebelled in 1173 were unable to provide a sufficient following of their own familiar knights, and relied instead on Flemish mercenaries.  At the same time the protection of seisin and movable property through the newly expanded common law, further reduced the executive authority of the barons over insubordinate sub-tenants, by severely restricting the power of distraint. 
By the early thirteenth century the feudal powers of some of baronage over their erstwhile feudal tenants were in terminal decline. William of Kentwell, Lord of Kentwell in Suffolk, admitted in l230 that he had lost control of seven of the ten fees of his honour, and no longer knew who held them, but as early as 1171 Ranulph Glanvill claimed to be unable to account for some of the fees on his honour of Eye. 
In the field of government the barons were very early excluded from the non-feudal areas of royal administration. Baronial control of shrievalties was the franchisal rights of their baronies. Tentative moves to separate the shrievalties from a feudal monopoly began under Rufus, with the appointment of county justiciars to keep a check on the sheriff, but most of the baronial shrievalties were swept away under Henry I, bringing the office of sheriff back within royal control under the direction of local knights, or curial officials of no more than knightly rank. Henry II's legal reforms required the active participation of the shire and communal courts, and gradually absorbed the rural knights into the business of both central and local government. Just as Henry II had himself distinguished between military and rustic knights, so also Ralph of Diceto could identify the new authority which came to the rural knights through service in the king's courts. This new status and authority in civil duties, together with the hereditary tenure of a manorial lordship, was the final impetus which diverted the warlike 'milites' into the new country gentry. Thus, by the mid-thirteenth century the greater barons had virtually abandoned the control of the shire courts to the gentry, and had ceased to command the allegiance of their vassals on anything other than a purely personal level. Whilst the country knights were still prepared to turn out behind the barons in the constitutional struggles of the thirteenth century, their political motivation flowed more from economic self interest than blind feudal obedience, sometimes with dire consequences. 
The joint separation of the crown and the gentry from the feudal hierarchy had two further effects on the political and constitutional framework. Firstly, the simple feudal relationship between the king on one side, and the tenants in chief and their vassals on the other, was replaced by a tripartite political structure consisting of the king, the barons, and the relatively independent gentry, corresponding to the dissociated feudal ranks. This structure afforded the constituents of political choice and combination in areas of possible conflict between the king and the baronswhere both could compete for the support fo the gentry as Henry III amd Simon de Montfort did over the assembly of Septmebr 1261. . Secondly the development of an impersonal crown created the constituents of constitutional choice by allowing the possibility of conflict over the proper control of the agencies of government. Thus, by the end of the twelfth century it is possible to distinguish between mere feudal rebellion, and constitutional rebellion arising between several political elements in combination, and directed at the control or supervision of the government, if not of the king himself.
These three factors, legal innovation, military innovation and political dissociation, may all be attributed to the rooting of the knight class on the land, from the eleventh century onwards, and to the strength and general peacefulness of English government which allowed successive generations of mesne tenants to consolidate their hold on the land. At the same time the expansion of fiscal and judicial institutions invested the knights with new civil duties which rapidly supplanted their old military ones. The reign of Henry II, therefore, marks the end of the first phase of enfeoffment and decay, and the initiation of a new phase of social and political reconstruction based on the king and the realm, rather than upon the static feudal hierarchy.IIOnce set in motion the symbiosis between institutional innovation and social change gathered momentum rapidly. Continued fiscal and judicial developments during the course of the thirteenth century brought about further changes within the knight class, consolidating the gentry element and transferring the military aspects of knighthood to the baronage. The course of these changes, and their effects on both the gentry and the constitution, may now be considered in more detail.
Although the king was clearly a feudal lord to his barons, he also possessed a residuum of undefined prerogative over and above the normal rights of a feudal lord. The operation of this prerogative fell within the exceptional powers required for the general goverment and utility of the realm, but it also included a large area of quasi-equitable jurisdiction available to the community only through the will of the king, and supplementary to the protective aspects of both common and feudal law. The ability of the king to use this executive prerogative was initially limited by the alienation, or usurpation, of royal rights by the companions of the Conqueror. Franchisal privileges thus alienated were gradually repossessed or transformed into obligations licensed and enforced by an increasingly powerful and omnicompetent crown. Alternatively this residual authority could issue in prescriptive legal processes accessible to the subject through the medium of writs actionable in the royal courts. During the reign of Henry II executive justice began to effect changes in the rights and remedies available to subjects, either as an alternative to remedies already offered by feudal custom, or as a superior form of justice in direct and successful competition with seignorial courts. By the age of Bracton men expected and demanded royal omnicompetence in the dispensation of justice; as Bracton says, 'it is the king's business to provide a competent remedy for every wrong'. 
Since the prescriptive aspects of this executive justice operated through the machinery of the communal courts and the common law, increasing use was made of the communal agencies of government. These in turn acquired an organisation and cohesion which enabled them both to make communal decisions and to further communal aims in relation with the central government. At the beginning of the twelfth century the shire was little more than the sheriff; by the beginning of the thirteenth it had again become a community, which was increasingly led by the local gentry acting as more or less voluntary agents of royal, as opposed to feudal, local government.
As the formalisation of royal intervention in the common law modified or created the agencies through which it might operate at a local level, so also it required the development of an administrative bureaucracy to seal, issue and account for writs. Although these functions could be discharged by the royal household, itinerant and absentee kings in the late twelfth century necessarily allowed departments dealing with routine matters of government to separate from the household, and to acquire a considerable degree of autonomy. Under, but without, Richard, progress was made in the creation of departmentalised offices of state holding their own authorising seals, and subject to some form of conciliar control. The consolidation of these departments prepared the machinery with which later kings, more circumscribed to English affairs, might begin an assault on the feudal boundaries to royal prerogative. They also presupposed a separation of royal government from immediate royal control. This in turn prepared the ground for later struggles between the king and the magnates over the direction of government.
Pressure from below thus obliged the royal administration to expand, not unwillingly, into the area of common law, in response to demands for equity and protection; the inexorable claims of the governed on the obligations of government.  It was, moreover, the bounden duty of the king to protect the rights of his subjects; a condition of his coronation oath, and a rationale for his legislative and judicial authority at every level. In this respect the king was inevitably involved in reconciling past customs with present practices. The knights, for their part, were also required to operate part of the judicial system, and were increasingly invested with powers of local government and investigation under royal authority.
The formation of the common law, and its sale through the medium of chancery writs, led to further administrative feedback by passing on to the sheriff extensive supervisory duties, and obliging him to account for the profits of royal justice in his shrievalty. Similarly the popular extension of royal justice to persons other than tenants in chief led to a proliferation of the small debts of small litigants and a corresponding improvement in the machinery of the exchequer to cope with the rapidly increasing revenues of the royal courts. By the end of the twelfth century the problem created by expansion had become acute. Sustained pressure of demand for royal judgments obliged John to continue the expansion of the common law whilst also maintaining a balance between the sanctions of custom, the limits of the law, and his own formless prerogative which could provide an easy but arbitraary solution to cases which might otherwise be insoluble. The first major constitutional conflict between the king and the barons thus arose, in part, over the extent to which royal prerogative could operate as a supplement to, or in opposition to, feudal and customary law. It took the form of a prescriptive definition of the limits of royal action coupled with an implicit demand for a return to the more trustworthy system of Henry II. In this sense, therefore, Magna Carta fell within the feudal context of medieval kingship, rather than the fiscal and domanial context, which was to be the major area of constitutional conflict in the thirteenth and fourteenth centuries. 
A corollary of the proliferation of government departments administering the judicial aspects of royal prerogative, was the evolution of a conciliar body to coordinate the activities of government. The form of conciliar government which developed after the reign of Henry II operated generally in a political and advisory capacity, except during the absence or minority of the king, when it acquired executive and legislative powers comparable with those of the king himself. The development of a form of conciliar government created an additional context through which baronial opposition to royal policy might find expression. The subsequent history of the council is largely divided between the progressive consolidation of the Chancery and Exchequer into distinct executive departments, supervised and coordinated by the council, and the struggle within the remaining supervisory council to maintain an equitable balance between ministerial and baronial councillors. This struggle contributed very considerably to the development of the supervisory functions of parliament.
Another important aspect of the council was its assumption of some of the functions of equity and judicial redress properly exercised by the king himself. The specialisation of the common law brought about a contraction of the sources of redress in special cases, and the increasing impersonality and inaccessibility of the king advanced the chancellor as the chief source of equity apart from the king himself. Alienation to the chancery of certain prerogative rights of undefined equity had far reaching results. In particular the issue of writs to cover cases not covered by existing precedents or customs amounted in effect to substantive legislation, and could be opposed by the barons on the dual grounds that it was contrary to feudal custom, and that it was not authorised by the king with the counsel of his feudal advisors. A further factor was that the barons themselves had failed to develop any form of appellate jurisdiction equal in authority to that of the crown, so that the attractions of common law had further reduced the link between barons and their tenants. The rapid elaboration and sophistication of the royal judicial system thus created a serious problem of authorisation, one solution to which could also be found in the developing institution of parliament.
The elaboration of the judicial machine also created other problems, equally serious, and of a quite different kind. Sustained demand for royal justice, and the gradual elimination of alternative forms of justice, formalised the royal judicial administration and increasingly circumscribed common law procedure within the terms of an expanding repertoir of writs. The use of writs, and the precedents of case law' cut through the hard cake of feudal custom', but they also distilled out of the courts those cases which were too complicated or novel to be redressed by existing procedures. An inevitable consequence of the systematization of the common law was that the defects of the system were progressively revealed and a demand developed either for a higher system of equity to cover unique cases, or for a major modification of the law to cover contingencies beyond the scope of the existing system. The normal procedure during the mid-thirteenth century was, in the first instance, to seek redress by direct petition to the king, or, in the second instance, to have pleas which were beyond the competence of individual judges respited to the new coming parliament for consideration by the council. In both cases legal redress was sought through the direct intervention of the king, or of his council, offering a 'complementum justitiae', and the occasion for this form of redress appears to have been a parliament which included a colloquium of courts. Although this early function of parliament clearly served the interests of litigants and petitioners, it did not entail any general form of representation, except insofar as the local courts might be required to send knights bearing the records of a specific case under the consideration of the parliament. This form of administrative liaison, based on the procedural requirements of the royal courts, was established as a corollary of communal presentments before itinerant justices, but it differs from parliamentary representation in that the knights thus summoned attended parliament as material witnesses, rather than as representatives. Nevertheless the work of the courts accustomed the local knights to attending the king's council and prepared them for the short further step to parliamentary representation.
The solution of difficult pleas by a colloquy of justices acting in the context of a parliament continued the process of distillation and refinement by which the most difficult and fundamental legal problems were separated, as they emerged, from those which could be dealt with by existing law, or by the issue of original writs. It follows that the most difficult cases were necessarily those which entailed the maximum extension of royal executive prerogative, and therefore, also, were most likely to entail major changes in the existing law. Thus the king's ability to authorize further substantive legislation by the issue of new writs was increasingly limited by demands that major alterations in the existing law required the approval of the baronage. The formalised system of common law, in addition to the precepts of Magna Carta, now provided a standard against which further extensions of royal authority might be recognised, judged, and, if necessary, checked. The informal elaboration of the law thus increasingly inhibited further elaboration.
One solution to the problem of authorising legal innovation was to enact the necessary changes in parliament, in full view of the baronage, at least, and to issue further substantive law in the form of comprehensive statutes. The promulgation of statutes reduced the scope for original writs, and the procedure for such issue was itself modified by statute to allow basically similar cases to proceed by writs issued 'in consimili casu'. The rationale for statute legislation is adequately summarised by the preamble to the second Statute of Westminster, that:-
He [the king]ordained certain statutes very necessary and useful for his people of England and Ireland, who were subject to his rule, so that they obtained more speedy justice in their oppressions than they had before. Nevertheless, certain cases in which the law was deficient have remained undetermined, whilst others for the reformation of the oppression of the people remain to be enacted.
There is no reason to doubt the honesty of the drafters. 
The development of the legislative functions of parliament followed from the considerable, but amorphous, demand for law making coming from below; 'parliaments were at once the field in which such impulses could work, and, as time went on, the institution by which men could assert and enlarge their claim to law and justice'. But a condition of the legislative function of parliament was that only the most important changes in the law required emendation by statute, although statutes could be far reaching at every level, and since such changes were national in character the process of revision and authorization could best be enacted in parliament. Moreover, once committed to major modifications of the law by statutory legislation kings passed on to their posterity an inexhaustible fund of conflicts and confusions of interpretation as new judges wrestled with old statutes. The promulgation of the first comprehensive statute thus set in perpetual motion a complex machinery of revision and emendation to keep the law in step with changing conditions. As the fourteenth century progressed it was increasingly agreed that such revision was best undertaken in parliament. In this sense, therefore, legislation created the momentum which carried parliament forward.
The removal of the most complicated categories of pleas to the cognizance of the king and the council in parliament provided one stimulus for legal developments initiated from below. An alternative procedure was to petition the king directly for redress of grievances, where no action existed at common law. During the formative period of the common law, redress, where appropriate, could be obtained by the issue of an original writ or administrative ordinances under the personal or delegated authority of the king, or, if the case was too difficult, by the king and his judges. In the mid-thirteenth century, therefore, petitions which revealed deficiencies in the common law might result in substantive legislation by writ, but, as with respited pleas, the formalisation of a system of remedies by writ sifted out all but the most difficult cases. No doubt many petitions were trivial requests for favours or complaints against royal officials, nevertheless petitioners apparently sought redress explicitly in parliament, and it is likely that some of the judicial, as opposed to legislative work of parliament arose from petitions.  Parliament, therefore, provided a means of access to the king, and to his royal judgement, and the occasion of parliament was also the occasion for a spate of petitions .
Most petitions however, sought judicial or executive action which could, in fact, be provided outside parliament. The flow of petitions into parliament was diverted in l280 and l293 by two administrative ordinances which directed all but the most important petitions through a panel of receivers and triers and thence to the government department most appropriate to the nature of the petition, either to Chancery, or to the Exchequer, or to the Justices. The general policy in the parliaments of Edward I was apparently to exclude from parliament all those petitions which sought merely judicial or executive action, and thus to keep parliament free for the weighty business of the king and kingdom, which might well include legislation. 
Petitions therefore were not a major factor in the promotion of parliamentary legislation, although it is also clear that certain statutes did arise explicitly from grievances brought forward in petitions. This is particularly true of the period after the issue of the great reforming statutes, when remaining defects in the law were rectified by minor statutes drawn up in response to petitions and other information from below. During the fourteenth century the development of the commons petition played an important part in the evolution of the lower house. 
Nor is it evident that the representatives of the shires and towns acted as a medium for the presentation of petitions, either as individuals, collectively, or on behalf of their localities. The use of petitions by the commons as a means of exerting pressure for legislation or redress was still largely unformalized, even in the later fourteenth century, but in the reign of Edward III petitioning for general redress of grievances became more important and continuous, leading in l340 to the distinction of 'commune' from 'singular' petitions.
Nevertheless these aspects of the growth of the judicial and legislative functions of royal administration, and their repercussions on society in general, were initiated by general pressure from below, acting in concert with the king's desire to extend his own authority. Law at this period was a valuable and marketable commodity, and its eager consumers were the knights, barons and other free and prosperous men anxious to buy and sell land within the safeguards of the law. The result of this growth was to expand the royal monopoly of government to a point at which it persistently conflicted with feudal custom. But it also brought ever increasing numbers of people into some form of relationship with a central and national government, thus consolidating the lateral ties in society at the expense of the simpler vertical ties of the feudal hierarchy. Similarly baronial opposition to royal encroachments on customary privilege, or to the king's failure to operate the government in accordance with custom and right, increasingly claimed the sanction of the community of the realm. Such a claim might be based on the feudal notion that every subtenant was represented in the king's councils by his superior lord, but it also implied a society in which national interests were overtaking feudal allegiances.IIIThe development of the fiscal aspects of royal administration demonstrates a similar symbiosis, but in this case Government innovations in taxation served both to create new institutions and to accelerate the social and economic changes which they sought to tap. Although the expansion of royal justice proceeded in parallel with an existing system of feudal justice which it later replaced, the fiscal expedients open to the crown were more closely confined by feudal custom, especially after Magna Carta. Thus, any fiscal innovation undertaken by the crown was bound to entail modification of the feudal framework and was likely to precipitate constitutional conflicts where rights and customs were considered to be endangered.
The major royal revenues at the end of the twelfth century were of six basic kinds. Firstly the income from the royal demesne, secondly the three obligatory feudal aids, augmented by other feudal incidents such as reliefs, marriages, wardships etc. together with gracious aids and scutages. Thirdly, the profits of justice; fourthly the sale or licensing of rights of jurisidction, liberties, markets, charters etc; fifthly regalian rights and other profits accruing from the church, and sixthly the right to tallage tenants on the royal demesne and the prerogative right to customs duties. Of these sources of revenue only scutages and gracious aids had any potential for rapid development to meet extraordinary needs.
It has already been suggested that cash commutation of feudal obligations was a necessary alternative to corporal service where the subdivision of fields and the partition of baronies had compromised the practical operation of the feudal military system. In the case of many small or scattered holdings a cash payment was the only possible form of service. Nevertheless, by the end of the twelfth century the revenue from sutage was no longer adequate to meet the needs of the king. During the reign of Richard there was a considerable increase in the cost of armour and equipment, and a corresponding rise in the rates of pay for a fully armed professional knight. This increase could no longer be met by progressive increases in the rate of scutage. The ruralization of the lesser military tenants, well established by the reign of John, caused a corresponding reduction in the servitia debit of baronies, and an increase in the number of persons compounding for service either by paying scutage at the traditional rate through their superior lord, or else offering a fine for exemption paid directly to the exchequer. Under John the customary procedure of levying scutage from subtenants through the medium of their superior lords was often bypassed in favour of a direct levy exacted from all subtenants by the sheriff. The consequence of these and other exactions was to force a constitutional conflict through which, amongst other things, the extent of commuted obligations was precisely fixed. This in turn emphasised and aggravated the failings of the fiscal exploitation of obligations, and forced upon future kings the necessity of finding a more regular and progressive source of income.
Whilst Magna Carta closed the door on progressive scutage rates, rapid economic change in thirteenth century society created new openings for alternative sources of revenue. During the first phase of feudalism attempts to exact practical military service from mesne tenants had been compromised either by subinfeudation and alienation, or by the minority, incapacity or the sheer unwillingness of knightly tenants to fulfil their obligations in person. During the second phase of feudal development an attempt was made to convert practical military service into fiscal obligations, the proceeds from which could be used to hire mercenaries. If the income from scutage could no longer be raised by increasing the rates, it might be raised by spreading the burden. This fiscal feudalism was facilitated and eventually compromised by the economic development of the knights from the twelfth century onwards.
By the mid-thirteenth century the average descendant of the Norman milites had acquired new and distinct characteristics, emerging as a fully fledged country gentleman, professional landowner, seignorial lord, local administrator, royal justice and occasional amateur soldier. These changes were made in the context of the economic boom of the late twelfth and the thirteenth centuries,  the general characteristics of which may be summarised as follows. Royal control and encouragement of boroughs in the twelfth-century England served to expand agriculturally dependent urban communities and thus stimulated changes in the manorial and peasant economy to meet a rising demand for food. Since the expansion of agriculture necessarily entailed increased pressure on land, both food prices and rents rose appreciably, so that those who possessed land could profit both by selling produce and by letting out their lands. Those without land served as an increasing pool of hired labour, which further augmented the market for food. These conditions particularly favoured the newly emerging gentry whose compact estates were in many ways more amenable to intensive exploitation than the more dispersed estates of the greater magnates. The response of the manorial economy to the joint phenomena of a population and price rise was thus to intensify the exploitation of demesne land and to increase the pressure on villein tenants either by exacting maximum labour services, or commuting their services to cash payments then used to hire wage labour. 
By the last quarter of the thirteenth century the period of high farming had begun to run up against certain limited factors which increasingly restricted the economic progress of the landowning classes, and reduced the poorer classes to subsistence, starvation, and eventually to plague and death. The reaction of the gentry and nobility to this increasing pressure has become a matter of controversy, since certain categories of evidence suggest that the greater magnates were repossessing the estates of the knightly tenants who were in consequence losing ground territorially.  The evidence for this assertion, while indisputable in itself, is biased towards the well-documented estates of the great ecclesiastical landowners who were better equipped to keep records of acquisitions than lesser men whose activities in the land market might well go unrecorded. Alternatively the sale of land to the greater landowners may represent nothing more than a pruning of the weaker elements in the gentry whilst the more substantial and secure gentry consolidated their estates, leased out remote holdings, and tightened their belts. The resolution of this particular problem awaits a more systematic investigation of the economic activities of the gentry class as a whole.
Economic pressure at the end of the thirteenth century affected both king and subjects alike, and contributed to the constitutional disturbances which soured the later years of Edward I. Economic expansion at the beginning of the century produced other effects which brought the activities of the gentry within the purview of the crown.
Firstly, during the earlier stages of the boom, manorial demesnes were expanded,  partly through accretions of escheats and dowries, but mainly through the sale and purchase of land. The ability to buy up land was in itself a function of the new wealth of the gentry. The growth of a land market maintained and amplified the demand for legal judgment and protection, and, as has already been suggested, it also necessitated considerable readjustment of the common law to reconcile the many complexities of conveyancing with the inadequacies of existing land law. Moreover economic progress encouraged the gentry to acquire new skills. The demands of estate management obliged them to learn something of the law, the keeping of accounts, the management of property, and other entrepreneurial talents which greatly widened their field of interest. Together with their property and their status these skills also suited them particularly well to the duties of local government, and, conversely, their experience of serving the king in local government might further their own private interests. 
Secondly, the gradual concentration of wealth in the hands of the knights emphasized the disparity between their incomes and their obligations. Although many may have been unwilling or unable to maintain the full military equipment of the belted knight, now almost a prerogative of the higher nobility, the cash equivalent of their obligations amounted to little more than an addition to the rent. Henry III, pious and pusillanimous, encouraged the arts of peace and permitted fines for respite of knighthood. As a result the limitations of a system of taxation based upon the commutation of feudal obligations became increasingly evident, and by the mid-thirteenth century steps were being taken to increase the yield by varying the basis of obligation. This was done by demanding that all who held lands owing knight service should take up the status and obligations of knight. The first major distraint of knighthood, ordered in l224, attempted to enforce knighthood on both tenants in chief, and tenants paravail, but later writs, up to l240, were limited to tenants in chief alone. Orders for the distraint of knighthood were closely linked with the foreign enterprises of the crown, and were clearly intended either as a means of increasing revenue through scutage, or of increasing the number of proffers of cavalry service. By l240 the basis of assessment had again been extended to impose the obligations of knighthood on all military or socage tenements equivalent to one fee, or part of a fee. This was probably a cautious preliminary to a more inclusive order in l24l which extended the basis of distraint from a purely tenurial obligation, to a property or income qualification falling upon all holding land worth 20 librates per annum, either in knights fee or socage. Whilst this undoubtedly spared the poorer military tenants, it thrust new burdens onto men who were not properly knights at all. The possibility of a joint criterion of knighthood based either on tenurial obligations, or upon an indefinite and flexible property or income qualification, was affirmed by the articles of the l254 Eyre, through which distraint of knighthood was to be enforced. Official recognition of the military obligations of persons other than strictly feudal tenants had the effect of dissociating the obligations of knighthood from the conditions of tenure, thus exposing all wealthy freeholders to the military obligations and status of knighthood. Since this status could, in practice, be avoided at will by the payment of a fine the military aspects of knighthood were thrown into sharp relief. A knight was no longer necessarily a man owing military service for his land, but rather one who was able to live like a knight, maintaining the proper horses and equipment, and regularly pursuing the arts of war. The belted knight was thus distinguished from his country cousins whose claim to knighthood rested on quite different characteristics.
The final expedient in the fiscal exploitation of feudal obligations thus tended to reinforce the new economic and social characteristics of knighthood, and encouraged the ultimate dissociation of the gentry from the feudal hierarchy. It also helped to ensure that the knights who were eventually summoned to parliament would be summoned not as a feudal estate, but as a social class defined by property rather than tenure.
The extent to which feudal obligations could be exploited as a fiscal device was, inevitably, progressively limited. By the mid-thirteenth century the yield from scutage, even on the wider basis of a property qualification, was insufficient to meet the needs of the crown, and the mode of authorisation for the levying of scutage excluded a significant proportion of those who were expected to pay it. Moreover the history of scutage was interrupted for nearly twenty years by the barons' wars, and its effective collection, through the medium of the tenants in chief, appears to have declined after l242, probably as a consequence of the declining authority of seignorial courts over erstwhile military sub-tenants. 
Although both scutage and distraint of knighthood were resumed and vigorously exploited during the final quarters of the century, other expedients began to emerge, of which the most promising was the general tax on movable property granted, initially at least, under the guise of a gracious aid. Various experiments had already been conducted with taxation based on knight's fees, or on ploughs, as in ll98, and a tax on movableproperty was imposed on the nobility in l203, setting a precedent for the first general tax on movables imposed in l207. The disadvantage of this form of taxation was that, unlike scutage, it was a voluntary or gracious aid which could only be authorised by the consent of the magnates, and this could, as in l237, be refused. The advantage of lay subsidies was that they fell on all men irrespective of status or tenure, and thus corresponded more closely with social and economic realities. In addition the collection of such aids could be organised on a national rather than a feudal basis, thus further expanding the royal bureaucracy at both national and local levels. As with the national extension of the common law, the collection of national lay subsidies again strengthened the lateral ties in society, bringing all property holders into a direct relationship with the central government. Similarly, the assessment and collection of such taxes was entrusted to the local knights, further adding to their burdens and responsibilities.
The fiscal and legal aspects of royal government were thus encouraged by, and in response to, the social and economic development of the gentry in the thirteenth century. The conditions were created in which the institutions of parliament could develop. The third factor to be considered in this development is the changing political framework of the thirteenth century. The third factor to be considered in this development is the changing political framework of the thirteenth century.
The relationship between the expanding judicial and fiscal activities of royal government, and the existing feudal institutions and practices appears to have reached a critical point in the mid-thirteenth century. At this period the constituents of constitutional conflict had become apparent, and the feudal hierarchy was sufficiently fragmented for the various ranks and classes to take sides in pursuit of independent aims. According to Jolliffe even John had sought the support of the counties against his treacherous barons, and it is quite clear that the knights who took part in the Barons'Wars in the reign of Henry III did so as much to further their own interests, as out of blind allegiance to feudal superiors. There is no doubt that by the mid-thirteenth century the political and administrative support of the men of the counties was well worth having. During the reign of Henry III each shift in the balance of political power was accompanied by a change of local officials. The Provisions of Oxford amply demonstrate the reliance of the baronage on the support of the local gentry for the implementation of their reforms. The political conditions of the mid-thirteenth century were thus in part created by, and parallel with, social and economic changes which were national and anti-feudal in temper. By the mid-thirteenth century the feudal aspects of baronial opposition to the king were rather less evident than their demands for good government consistent with the needs of the time. The barons had themselves controlled the government during the minority of Henry III and the first major constitutional conflict of the reign followed upon their gradual exclusion from executive power by royal ministeriales and favourites. Baronial objectives were no longer limited to the maintenance of feudal spheres of influence, but encompassed the king's right to govern at all, without the co-operation of at least the greater magnates. In practice the sophistication of mid-thirteenth century government necessitated a permanent and professional council rather than an occasional assembly of barons exercising vague supervisory power, and continually clashing with the traditions of bureaucratic and ministerial counsel. In any case close baronial supervision could always be circumvented through the medium of the king's private household which could displace the functions of a baronially controlled Chancery and Exchequer. 
In addition to demonstrating the national character of political issues the crisis of l250-l264 showed a clear need for an occasional assembly, meeting at a higher level than the Council, in which the king and the barons could discuss the general principles and supervise the policies of royal government.  Political conditions demanded such an institution, and the reformers of l258 clearly conceived of parliament in these terms. However political problems could well be resolved by the king and the barons alone, meeting together in a conciliar parliament in which the greater barons represented the lesser, and, by virtue of their lordship also represented all other classes. Even before the second half of the thirteenth century it was evident that finance was at the root of most constitutional issues. Whilst the political opposition of the baronage might limit the king's more extravagant projects, the regular machinery of government and the extraordinary financing of war were beyond the resources of the king and the barons alone. The interrelation of politics and administration therefore moved towards an extension of the fiscal functions of parliament which could best be achieved by including representatives of the non-feudal classes acting on behalf of the communities of the shires and towns.
The association of the gentry with parliament followed also from the increasing inability of the barons to answer for their subtenants in consenting to aids. There was no legal necessity for seeking the assent of those upon whom the taxes were to fall, but the co-operation of the taxpayer was essential, since lay subsidies were assessed and collected through the machinery of a gentry controlled local administration. This co-operation could best be achieved by offering the taxpayers a nominal assent to the rate of taxation by summoning shire and borough representatives to parliament. More important however was the use of parliament as a means of representing the views of the central government back to the people by using the representatives as propagandists for royal policy. Parliament in this sense provided a means of liaison between the central and local aspects of royal administration, bringing the crown into direction relations with the realm. 
Under Edward I parliament became the normal means of authorising gracious aids, which were in consequence transformed from their feudal origins into genuine national taxes binding upon all men, through the assent of their representatives in parliament. A corollary of demanding full and binding powers of assent from the knights of the shire and the burgesses was that the limited and conditions obligations of individual feudal grants of aids were superseded by the unconditional and corporate obligations of the parliamentary grant.  In this respect parliament acquired an identity quite distinct from that of the feudal great council alone. Individual magnates could, and did, refuse to grant an aid on the grounds that they had not been present at the granting body, but this refuge was not available to the communities of the shires. Furthermore royal justification of parliamentary taxation increasingly construed national necessity as the basis for national obligations, where the safety of the realm was endangered the king claimed a superior right to demand an aid for the common utility and public safety. 
Such appeals to national necessity were also consistent with the transference of political and military activity from essentially internal struggles under Henry III, to external or border wars under his son. The tentative development of a national army of foot soldiers under Edward was an important factor in the extension of national obligations, and of national consciousness. The traditional duty of all free men to bear arms could thus be used to encourage and foster the new doctrine of a national state, personified by a king to whom all owed service in times of common need. 
Political, fiscal and legal requirements during the last half of the thirteenth century thus all moved towards a national concept of the realm, and created the necessary conditions for the development of a national assembly in which representatives of the non-feudal classes were included as expedient, if not actually essential. The role of the gentry in each aspect of the development of parliament was crucial. Their need for new and better law created both the impulse for legal reform and the market for reformed law. Their dissociation from the obligations of feudal tenure encouraged both a new and national fiscal system, and the first steps towards a new and national military system. Representative liaison between central and local government, operating through the medium of parliament, secured for Edward I the support of the gentry class, and drew them inexorably into the fabric of national government. Successive parliament after l250 thrust an ever increasing burden of administrative duties upon the local gentry.  Successive wars after l290 revived their military obligations and further burdened them with the double yoke of fiscal feudalism and parliamentary subsidies.
Finally, the whole trend of royal policy towards local government, from the reign of Henry II onwards, had been to increase the independence, authority, and self-reliance of the local gentry in order to bring the counties more directly under royal control, both as a political counterweight to the baronage, and as a cheap and effective means of ruling the county. By the reign of Henry III these habits of self-government were deeply ingrained within the ruling groups in the counties, and Henry's attempts to replace local officials with royal favourites were undoubtedly sufficiently resented to cause many of the gentry to align with the barons in their struggle for reform. Demand for local control of local government thus became a significant issue in the constitutional struggles of the mid-thirteenth century. No king after Henry III, not even the masterful Edward I, could afford to take the country gentry for granted. They were a significant power in the land. By the end of the thirteenth century self-government had become a privilege well worth maintaining, even if it was only to be exercised under the king's stringent command.