St Thomas Becket 

1120 - 1170) was Archbishop of Canterbury from 1162 until his murder in 1170. He is venerated as a saint and martyr by both the Catholic Church and the Anglican Communion. He engaged in conflict with Henry II, King of England, over the rights and privileges of the Church and was murdered by followers of the king in Canterbury Cathedral. Soon after his death, he was canonised by Pope Alexander III.

Becket was born about 1120 in Cheapside, London, on 21 December, which was the feast day of St Thomas the Apostle. He was the son of Gilbert and Matilda Beket who were  of Norman descent. Gilbert began his life as a textile merchant, but by the 1120s he was living in London and was a property owner, living on the rental income from his properties. He also served as the sheriff of the city at some point.

Plaque marking Becket's birthplace along Cheapside

One of Becket's father's wealthy friends, Richer de L'Aigle, often invited Thomas to his estates in Sussex where Becket was exposed to hunting and hawking. Becket learned much from Richer, who was later a signatory of the Constitutions of Clarendon against Thomas.

Beginning when he was 10, Becket was sent as a student to Merton Priory in England on the old Roman road to Chichester (Stane Street) and later attended a grammar school at St Paul's Cathedral. Later, he spent about a year in Paris around age 20. He did not, however, study canon or civil law at this time and his Latin skill always remained somewhat rudimentary. Some time after Becket began his schooling, Gilbert Beket suffered financial reverses, and the younger Becket was forced to earn a living as a clerk. Gilbert first secured a place for his son in the business of a relative Osbert Huitdeniers and then later Becket acquired a position in the household of Theobald of Bec, by now the Archbishop of Canterbury.

Theobald entrusted him with several important missions to Rome and also sent him to Bologna and Auxerre to study canon law. Theobald in 1154 named Becket Archdeacon of Canterbury. His efficiency in those posts led to Theobald recommending him to King Henry II for the vacant post of Lord Chancellor, to which Becket was appointed in January 1155.

As Chancellor, Becket enforced the king's traditional sources of revenue that were exacted from all landowners, including churches and bishoprics. King Henry even sent his son Henry to live in Becket's household, it being the custom then for noble children to be fostered out to other noble houses. Becket was nominated as Archbishop of Canterbury in 1162, several months after the death of Theobald. His election was confirmed on 23 May 1162 by a royal council of bishops and noblemen. Henry may have hoped that Becket would continue to put the royal government first, rather than the church. However, the famous transformation of Becket into an ascetic occurred at this time.

A rift grew between Henry and Becket as the new archbishop resigned his chancellorship and sought to recover and extend the rights of the archbishopric. This led to a series of conflicts with the King, including that over the jurisdiction of secular courts over English clergymen, which accelerated antipathy between Becket and the king. Attempts by Henry to influence the other bishops against Becket began in Westminster in October 1163, where the King sought approval of the traditional rights of the royal government in regard to the church. This led to the Constitutions of Clarendon, where Becket was officially asked to agree to the King's rights or face political repercussions.

King Henry II presided over the assemblies of most of the higher English clergy at Clarendon Palace on 30 January 1164. In sixteen constitutions, he sought less clerical independence and a weaker connection with Rome. He employed all his skills to induce their consent and was apparently successful with all but Becket. Finally, even Becket expressed his willingness to agree to the substance of the Constitutions of Clarendon, but he still refused to formally sign the documents. Henry summoned Becket to appear before a great council at Northampton Castle on 8 October 1164, to answer allegations of contempt of royal authority and malfeasance in the Chancellor's office. Convicted on the charges, Becket stormed out of the trial and fled to the Continent.

Henry pursued the fugitive archbishop with a series of edicts, targeting Becket as well as all of Becket's friends and supporters, but King Louis VII of France offered Becket protection. He spent nearly two years in the Cistercian abbey of Pontigny, until Henry's threats against the order obliged him to return to Sens. Becket fought back by threatening excommunication and interdict against the king and bishops and the kingdom, but Pope Alexander III, though sympathising with him in theory, favoured a more diplomatic approach. Papal legates were sent in 1167 with authority to act as arbitrators. In 1170, Alexander sent delegates to impose a solution to the dispute. At that point, Henry offered a compromise that would allow Thomas to return to England from exile.

In June 1170, Roger de Pont L'Évêque, the archbishop of York, along with Gilbert Foliot, the Bishop of London, and Josceline de Bohon, the Bishop of Salisbury, crowned the heir apparent, Henry the Young King, at York. This was a breach of Canterbury's privilege of coronation, and in November 1170 Becket excommunicated all three. While the three clergymen fled to the king in Normandy, Becket continued to excommunicate his opponents in the church, the news of which also reached Henry II, Henry the Young King's father. Upon hearing reports of Becket's actions, Henry is said to have uttered words that were interpreted by his men as wishing Becket killed. The king's exact words are in doubt and several versions have been reported. It may be "What miserable drones and traitors have I nourished and brought up in my household, who let their lord be treated with such shameful contempt by a low-born cleric” Whatever Henry said, it was interpreted as a royal command, and four knights,[12] Reginald FitzUrse, Hugh de Morville, William de Tracy and Richard le Breton, set out to confront the Archbishop of Canterbury. On 29 December 1170, they arrived at Canterbury. According to accounts left by the monk Gervase of Canterbury and eyewitness Edward Grim, they placed their weapons under a tree outside the cathedral and hid their mail armour under cloaks before entering to challenge Becket. The knights informed Becket he was to go to Winchester to give an account of his actions, but Becket refused. It was not until Becket refused their demands to submit to the king's will that they retrieved their weapons and rushed back inside for the killing. Becket, meanwhile, proceeded to the main hall for vespers. The other monks tried to bolt themselves in for safety, but Becket ordered them to reopen the doors. The four knights, wielding drawn swords, ran into the room and found Becket, cutting off the top of the crown then received a second blow on the head then a third knight inflicted a terrible wound as he lay prostrate. By this stroke, the crown of his head was separated from the head.  Following Becket's death, the monks prepared his body for burial.  According to some accounts, it was discovered that Becket had worn a hairshirt under his archbishop's garments a sign of penance.  Soon after, the faithful throughout Europe began venerating Becket as a martyr, and on 21 February 1173 little more than two years after his death he was canonised by Pope Alexander III in St Peter's Church in Segni. On 12 July 1174, in the midst of the Revolt of 1173–74, Henry humbled himself with public penance at Becket's tomb.  Becket's assassins were not arrested and neither did Henry confiscate their lands, but he failed to help them when they sought his advice in August 1171. Pope Alexander excommunicated all four. Seeking forgiveness, the assassins travelled to Rome and were ordered by the Pope to serve as knights in the Holy Lands for a period of fourteen years.