Becket was one of those men who, without being either hypocrites or consciously ambitious, live only to magnify their office. While chancellor he was the most zealous servant of the crown, and had seemed rather secular than clerical in his habits and his outlook on life. But no sooner had he been promoted to the archbishopric than he put away his former manners, became the most formal and austere of men, and set himself to be the champion of the church party in all its claims, reasonable or unreasonable, against the state. The king's astonishment was even greater than his indignation when he saw the late chancellor setting himself to oppose him in all things.

Their first quarrel was about a proposed change in some details of taxation, which seems to have had no specially ecclesiastical bearing at all. But Becket vehemently opposed it, and got so much support when the great council met at Woodstock that Henry withdrew his schemes. This was only a preliminary skirmish; the main battle opened in the following year, when the king, quite aware that he must for the future look on Thomas as his enemy, brought forward the famous Constitutions of Clarendon, of which the main purport was to assert the jurisdiction of the state over clerical offenders by a rather complicated procedure, while other clauses provided that appeals to Rome must not be made without the king's leave, that suits about land or the presentation to benefices, in which clerics were concerned, should be tried before the royal courts, and that bishops should not quit the realm unless they had obtained permission to do so from the king. Somewhat to the king's surprise, Becket yielded for a moment to his pressure, and declared his assent to the constitutions. But he had no sooner left the court than he proclaimed that he had grievously sinned in giving way, suspended himself from his archiepiscopal functions, and wrote to the pope to beg for pardon and absolution. He then made a clandestine attempt to escape from the realm, but was detected on the seashore and forced to return.

Incensed with Becket for his repudiation of his original submission, Henry proceeded to open a campaign of lawsuits against him, in order to force him to plead in secular courts. He also took the very mean step of declaring that he should call him to account for all the moneys that had passed through his hands when he was chancellor, though Becket had been given a quittance for them when he resigned the office more than two years before. The business came up at the council of Northampton (October 1164), when the archbishop was tried for refusing to recognize the jurisdiction of the king's courts, and declared to have forfeited his movable goods. The sentence was passed by the lay members of the Curia Regis alone, the bishops having been forbidden to sit, and threatened with excommunication if they did so, by the accused primate. When Becket was visited by the justiciar who came to rehearse the judgment, he started to his feet, refused to listen to a word, declared his repudiation of all lay courts and left the hall.

That same night he made a second attempt to escape from England and this time succeeded in getting off to Flanders. From thence he fled to the court of the pope, where he received less support than he had expected. Alexander III privately approved of all that he had done, and regarded him as the champion of the Church, but he did not wish to quarrel with King Henry. He had lately been driven from Rome by the emperor Frederick I, who had installed an antipope in his place, and had been forced to retire to France. If he sided with Becket and thundered against his persecutor, there was small doubt that the king of England would adhere to the schism. Accordingly he endeavoured to temporize and to avoid a rupture, to the archbishops great disgust. But since he also declared the Constitutions of Clarendon uncanonical and invalid, Henry was equally offended, and opened negotiations with the emperor and the antipope. This conduct forced Alexander's hand, and he gave Becket leave to excommunicate his enemies. The exile, who had taken refuge in a French abbey, placed the justiciar and six other of the king's chief councillors under the ban of the Church, and intimated that he should add Henry himself to the list unless he showed speedy signs of repentance (April 1166).

Thus the quarrel had come to a head. Church and State were at open war. Henry soon found that Becket's threats had more effect than he liked. Many of the English clergy were naturally on the side of the primate in a dispute which touched their loyalty to the Church and their class feeling. Several bishops declared to the king that, since his ministers had been duly excommunicated, they did not see how they could avoid regarding them as men placed outside the pale of Christendom. Fortunately the pope interfered for a moment to lighten the friction; being threatened with a new invasion by the emperor Frederick, he suspended the sentences and sent legates to patch up a peace. They failed, for neither the king nor the archbishop would give way. At this juncture Henry was desirous of getting his eldest son and namesake crowned as his colleague, the best mode that he could devise for avoiding the dangers of a disputed succession at his death. He induced the archbishop of York, assisted by the bishops of London and Salisbury, to perform the ceremony. This was a clear invasion of the ancient rights of the primate, and Becket took it more to heart than any other of his grievances.

Yet the next move in the struggle was a hollow reconciliation between the combatants a most inexplicable act on both sides. The king offered to allow Becket to return from exile, and to restore him to his possessions, without exacting from him any promise of submission, or even a pledge that he would not reopen the dispute on his return. Apparently he had made a wrong interpretation of the primate's mental attitude, and thought him desirous of a truce, if not ready for a compromise. He had wholly misjudged the situation; Becket made neither promises nor threats, but three weeks after he reached Canterbury publicly excommunicated the bishops of London and Salisbury for the part that they had taken in the coronation of the young king, and suspended from their functions the other prelates who had been present at the ceremony. He then proceeded to excommunicate a number of his minor lay enemies.

The news was carried overseas to Henry, who was then in Normandy. It roused one of the fits of wild rage to which he was not unfrequently liable; he burst out into ejaculations of wrath, and cursed the cowardly idle servants who suffered their master to be made the laughing-stock of a low-born priest. Among those who stood about him were four knights, some of whom had personal grudges against Becket, and all of whom were reckless ruffians, who were eager to win their master's favour by fair means or foul. They crossed the Channel with astonishing speed; two days after the king's outburst they stood before Becket at Canterbury and threatened him with death unless he should remove the excommunications and submit to his master. The archbishop answered with words as scornful as their own, and took his way to the minster to attend vespers. The knights went out to seek their weapons, and when armed followed him into the north transept, where they fell upon him and brutally slew him with many sword-strokes (December 29, 1170). Thomas had been given time to fly, and his followers had endeavoured to persuade him to do so. It seems that he deliberately courted martyrdom, anxious apparently that his death should deal the king the bitterest blow that it was in his power to inflict.

Nothing could have put Henry in such an evil plight; the whole world held him responsible for the murder, and he was forced to buy pardon for it by surrendering many of the advantages over the Church which he had hoped to gain by enforcing the Constitutions of Clarendon. Especially the immunity of clerical offenders from the jurisdiction of lay courts had to be conceded; for the rest of the middle ages the clerk guilty of theft or assault, riot or murder, could plead his orders, and escape from the harsh justice of the king's officers to the milder penalties of the bishops tribunal. Benefit of clergy became an intolerable anomaly, all the more so because the privilege was extended in practice not only to all persons actually in minor orders, but to all who claimed them; any criminal who could read had a fair chance of being reckoned a clerk.

Another concession which Henry was forced to make was that the appeals to Rome of litigants in ecclesiastical suits should be freely permitted, provided that they made an oath that they were not contemplating any wrong to the English crown or the English church, a sufficiently easy condition. Such appeals became, and remained, innumerable and vexatious. Pope Alexander also extorted from the king a pledge that he would relinquish any customs prejudicial to the rights of the Church which had been introduced since his accession. To the pope this meant that the Constitutions of Clarendon were disavowed; to the king, who maintained that they were in the main a mere restatement of the customs of William I, it bore no such general interpretation. The points were fought out in detail, and not settled for many years. Practically it became the rule to regard suits regarding land, or presentations to benefices, as pertaining to the king's court, while those regarding probate, marriage and divorce fell to the ecclesiastical tribunal. The question of election to bishoprics and abbacies went back to the stage which it had reached in the time of Henry I; the choice was made in canonical form, by the chapters or the monasteries, but the king's recommendation was a primary factor in that choice. When the electors disregarded it, as was sometimes the case, there was friction; a weak king was sometimes overruled; a strong one generally got his way in the end.

Becket's death, then, gave a qualified triumph to the church party, and he was rightly regarded as the successful champion of his caste. Hence they held his death in grateful remembrance; the pope canonized him in 1173, and more churches were dedicated to him during the next two centuries than to any other English saint. In the eyes of most men his martyrdom had put the king so much in the wrong that the obstinacy and provocative conduct which had brought it about passed out of memory. His life of ostentatious austerity, and the courage with which he met his death, had caused all his faults to be forgotten. Henry himself felt so much the invidious position. in which he was placed that even after making his submission to the popes legates at Avranches in 1172, he thought it necessary to do penance before Becket's tomb in 1174, on which occasion he allowed himself to be publicly scourged by the monks of Canterbury, who inflicted on him three cuts apiece.

Between the outbreak of the king's quarrel with Becket at the council of Woodstock and the compromise of Avranches no less than ten years had elapsed the best years of Henry's manhood. During this period his struggle with the Church had been but one of his distractions. His policy of imperial aggrandisement had been in progress. In 1163 he had completed the conquest of South Wales; the marcher lords were now in possession of the greater part of the land; the surviving Welsh princes did homage for the rest. In 1166 Henry got practical possession of the duchy of Brittany, the only remaining large district of western France which was not already in his hands. Conan, the last prince of the old Breton house, recognized him as his lord, and gave the hand of his heiress Constance to Geoffrey, the king's third son. When the count died in 1171 Henry did not transfer the administration of the land to the young pair, who were still but children, but retained it for himself, and clung to it jealously long after his son came of age. Intermittent wars with France during these years were of small importance; Henry never pushed his suzerain to extremity. But the Angevin dominions were extended in a new direction, where no English king had yet made his power felt.

