Britannica Sources used in this answer

How did Thomas Becket die in Canterbury Cathedral?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

King Henry II and St. Thomas Becket — Henry II Henry II (left) disputing with Thomas Becket (center), miniature from a 14th-century manuscript; in the British Library (Cotton MS. Claudius D.ii).

On December 29, 1170, Thomas Becket, the archbishop of Canterbury, was murdered inside Canterbury Cathedral by four knights acting on the volatile frustrations of King Henry II.12

The conflict stemmed from a long-standing dispute over the rights of the Roman Catholic Church and Becket’s decision to excommunicate bishops who supported the king’s hostilities against papal authority. After forcing their way into the archbishop's presence and demanding he absolve the bishops, the knights followed him into the cathedral at twilight. Following a heated altercation, the knights attacked and killed him with their swords. Becket’s final words expressed his acceptance of death in defense of the church.12

The murder of a high-ranking cleric in a sacred space was a profound violation of religious and moral norms, leading to Becket's rapid canonization as a saint and martyr in 1173.12