 The rebels took an oath that they would "stand fast for the liberty of the church and the realm", and demanded that the King confirm the Charter of Liberties that had been declared by King Henry I in the previous century, and which was perceived by the barons to protect their rights.The rebel leadership was unimpressive by the standards of the time, even disreputable, but were united by their hatred of John; Robert FitzWalter, later elected leader of the rebel barons, claimed publicly that John had attempted to rape his daughter, and was implicated in a plot to assassinate John in 1212.John held a council in London in January 1215 to discuss potential reforms, and sponsored discussions in Oxford between his agents and the rebels during the spring.