It has been seen how Roman laws and institutions, which survived on the continent after the Teutonic conquest, failed to do so in the British Isles. The influence of the Roman law was to be felt, however, in England at a later period. Some slight knowledge of the Roman law came across with the lawyers who followed William the Conqueror after the Norman Conquest, but it was not until the next century that it began to exert any marked influence upon England. The twelfth century was throughout all Western Europe a century of revived interest and diligent study of the Roman law; it was lamented by some writers of that period, that all other branches of learning were neglected in the sudden enthusiasm for this study which had seized upon scholars. The early medieval laws of Western Europe, based upon corrupted codes of Roman law, still further corrupted by the infusion of the laws and customs of the Teutonic conquerors, were rapidly replaced by new scientific codes, based as closely as changed conditions would allow, upon the old Roman codes of Theodosius or Justinian. Roman law principles, moreover, were largely the basis of the new system of canon law administered in the ecclesiastical courts of the Church, whose jurisdiction was at this time being rapidly extended. It was in its two forms of the civil and canon law that the Roman law invaded England during this twelfth century, and for a time the extension of its influence, along both these lines, was very rapid. The ecclesiastical courts of the Church, administering the canon law, rapidly increased their jurisdiction; while the principles of the civil law became more and more resorted to by the judges of the King's courts in the regular settlement of the cases which came before them. For a time it seemed that what had been done in Western Continental Europe was about to be repeated in England, and her system of jurisprudence become merely a branch of the world wide Roman law. Roman law, however, was meeting in England a far more worthy contestant than it had hitherto encountered. The old English common law system, dating back into Anglo-Saxon times to the days of the seven kingdoms, numbering among its creators such men as Ine, Aelfred, and Dunstan; the combination of all that was best in the laws of the West Saxon, and Mercian, and the other kingdoms; enriched and strengthened by the work of Dane and Norman, had become a part of the very life of the English people. It was a system less scientific, less carefully worked out than the Roman law, but one containing within itself certain elements of rugged strength in which the old system was lacking. It was, moreover, a system adapted to the needs of the people and times in which it existed. The result was a resistance on the part of the English people to the Roman law, which saved for themselves their own national laws, and resulted in the existence of two great systems of laws in the world instead of one. The encroachments of the ecclesiastical courts were checked in 1164, when Henry II forced upon the Church the Constitution of Clarendon, which put definite limits upon the jurisdiction of these courts. The introduction of Roman law principles into the English law continued down to the Assize of Merton, in 1238, when, to a new proposal to change the English law to correspond with the Roman law, the barons of England returned their historic reply: "Nolumus leges Angliae mutare." (We do not wish to change the laws of England.) The contest between the Roman law and the English common law was now over and the English common law remained the victor in the field. The effect upon itself, of the contest, however, still remained. Not only had it been modified by the various Roman law principles which had been adopted, but it also had been affected in a diametrically opposite direction. The long and hard fought contest which the people of England had waged for their old English laws had had the natural tendency to greatly enhance their affection for those laws. The English common law had become something sacred; something not to be lightly altered; "nolumus leges Angliae mutare" had become the motto of the English people, and the result was that the English law became rigid, and ill adapted to meet newly arising conditions. Especially was this true in the field of the adjective law. As already stated there existed certain original writs, creating certain forms of relief, and if a person had a case which entitled him to receive one of these writs he could obtain relief; otherwise the law was powerless to aid him. It has been shown how the attempt to remedy this state of affairs by the twenty-fourth chapter of the Statute of Westminster II, granting to the 'clerks in chancery the power to issue writs "in consimile casu," failed, on account of the liberal interpretation of this statute which would have done much towards remedying this defect, not being given to it. The result of this state of affairs was the development of the system of equity jurisprudence described in the following chapter.