Thomas de Berkeley, 3rd Baron Berkeley Thomas de Berkeley, 3rd Baron Berkeley Thomas de Berkeley (c. 1293 or 1296 – 27 October 1361), "The Rich", feudal baron of Berkeley, of Berkeley Castle in Gloucestershire, England, was a peer. His epithet, and that of each previous and subsequent head of his family, was coined by John Smyth of Nibley (d.1641), steward of the Berkeley estates, the biographer of the family and author of "Lives of the Berkeleys". He was the eldest son and heir of Maurice de Berkeley, 2nd Baron Berkeley by his wife Eve la Zouche. In 1327 he was made joint custodian of the deposed
Joan de Geneville, 2nd Baroness Geneville worse privations having been locked up inside various religious houses with even less money at their disposal. Joan was transferred from Skipton to Pontefract Castle in July 1326. Mortimer and Isabella landed in England two months later in September 1326, and they joined forces with Henry, 3rd Earl of Lancaster. On 16 November, King Edward was taken prisoner and eventually murdered at Berkeley Castle, presumably by Mortimer's hired assassins. From 1327 to 1330, Mortimer and Isabella jointly held the Office of Regent for her son, King Edward III who was duly crowned following his father's death. Mortimer was made constable