When Queen Isabella took up arms against her husband in 1326 she was joined at once by the earl, who took a leading part in the proceedings against the king and his favourites, the Despensers, being Edward's gaoler at Kenilworth castle.
He acquiesced in the earl's dictatorship; left to his eldest son, Edward, the difficult task of reorganizing the royal party; marched with the Montfortians to Evesham; and narrowly escaped sharing the fate of his gaoler.
During the 140 days of his imprisonment there he wrote the marvellous Iambes (in alternate lines of 12 and 8 syllables), which hiss and stab like poisoned bullets, and which were transmitted to his family by a venal gaoler.
In June 1744 they were transferred to Kholmogory on the White Sea, where Ivan, isolated from his family, and seeing nobody but his gaoler, remained for the next twelve years.