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Why did Thomas Becket become known as a martyr?

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St. Thomas Becket Murder of St. Thomas Becket, illustration from an English psalter, c. 1200; in the British Library.

Thomas Becket became known as a martyr because he was murdered in Canterbury Cathedral on December 29, 1170, while defending the rights and authority of the Roman Catholic Church.12

The conflict arose from a long-standing dispute between Becket, the archbishop of Canterbury, and King Henry II regarding papal authority and the independence of the church from royal control. After Becket excommunicated several bishops who supported the king’s hostilities against the church, four knights confronted him in the cathedral. When Becket refused to absolve the bishops, the knights killed him. His final words expressed an acceptance of death in defense of the church of Christ.132

Following his death, his tomb quickly became a site of pilgrimage, and he was canonized by Pope Alexander III in 1173. His legacy as a martyr remains a significant subject in the history of church and state relations.2