‘The Becket Dispute’ (or ‘Controversy’) refers to the quarrel between Henry II and Thomas Becket, Archbishop of Canterbury, which dominated English ecclesiastical politics in the 1160s. It was a conflict with multiple dimensions: a clash of Church and State; a prolonged struggle between two prominent individuals; a close friendship turned sour. Although the dispute itself produced a substantial number of sources, the shocking nature of Becket’s death in 1170 prompted the creation of many more. The amount and detail of this surviving material – and the insights it gives into the personalities involved – make it a particularly immediate and appealing episode. In contrast, the values underlying the conflict seem rather alien today: it concerns the defence of autocratic power on the one hand and ecclesiastical privilege on the other. The Becket Dispute both brings us closer to the twelfth century and distances us from it.