Archbishop Stephen Langton
Following the death of Archbishop Hubert Walter on 13 July 1205, there was a a prolonged dispute over the succession between King John, a number of English bishops, the monks of Christ Church Canterbury and Pope Innocent III. Stephen Langton was not consecrated as Archbishop of Canterbury until 17 June 1207. Even then, King John refused to accept him and Langton was not installed at Canterbury until 1213 when the king finally made peace with the pope.
Despite having spent five years in exile from 1208-1213, on his return to England, Langton swiftly assumed an important political role.
He was one of the leading mediators in the barons' dispute with King John and in the negotiations at Runnymede. The first clause in Magna Carta confirmed 'that the English Church shall be free and shall have its rights undiminished and its liberties unimpaired', doubtless reflecting Langton's influence. It may also be thanks to him that the Articles of the Barons has survived, since he apparently took this document away for safe-keeping after the meeting at Runnymede ended.