Edward II of England formally ended Edward's reign. A proclamation was sent to London, announcing that Edward, now known just as Edward of Caernarvon, had freely resigned his kingdom and that Prince Edward would succeed him. The coronation took place at Westminster Abbey on 2 February 1327. Those opposed to the new government began to make plans to free Edward, and Roger Mortimer decided to move Edward to the more secure location of Berkeley Castle in Gloucestershire, where the former King arrived around 5 April 1327. Once at the castle, Edward was kept in the custody of Mortimer's son-in-law, Thomas Berkeley, and John Maltravers,
Margaret Mortimer, Baroness Berkeley Margaret Mortimer, Baroness Berkeley Margaret Mortimer, Baroness Berkeley (2 May 1304 – 5 May 1337) was the wife of Thomas de Berkeley, 3rd Baron Berkeley. She was the eldest daughter of Roger Mortimer, 1st Earl of March, the "de facto" ruler of England from 1327 to 1330, and his wife Joan de Geneville, Baroness Geneville. Margaret Mortimer was the eldest of the twelve children of Roger Mortimer, 1st Earl of March and Joan de Geneville, Baroness Geneville. Her paternal grandparents were Edmund Mortimer, 2nd Baron Mortimer and Margaret de Fiennes. Her maternal grandparents were Piers de Geneville, of Trim Castle