Upon the death of Theobald, Henry made Becket Archbishop. The friendship that Henry and Becket shared was put under immense strain when Becket voiced his opposition to Henry on a number of issues, most notably the canonization of the Bishop of Anselm and the constitutions of Clarendon.

Realising the extent of Henry's displeasure, Becket fled to France, and remained in exile for several years until his return in 1170.

On the 29th December, 1170, four knights, believing the King wanted Becket out of the way, confronted and murdered Becket in Canterbury Cathedral.

Becket was canonized in 1173.