Constitutions of Clarendon
Henry reacted by getting Becket and other English bishops to recognise sixteen ancient customs in writing for the first time in the Constitutions of Clarendon, governing relations between the king, his courts and the church. When Becket tried to leave the country without permission, Henry tried to ruin him by filing legal cases relating to Becket's previous tenure as chancellor. Becket fled and remained in exile for five years. Relations later improved, and Becket returned, but they declined again when Henry's son was crowned as coregent by the Archbishop of York, which Becket perceived as a challenge to his authority.