Thomas de Berkeley, 3rd Baron Berkeley was succeeded by Maurice de Berkeley, 4th Baron Berkeley (born 1320, date of death unknown), eldest son and heir from his first marriage. 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
Berkeley family docent and genealogist at the Berkeley Castle listed the Barclay clan as also descending from the de Berkeley clan through the matriarchal line Alice De Berkeley -- the woman who married Robert Fitzharding and restored the family's name. Additionally, historians on Scottish clans and surnames point out that the Barclay clan spelling moves into the Berkeley (pronounced Bar-Clay) spelling. This descends from Sir Maurice Berkeley (by 1514–81), a politician who rose rapidly in the Tudor court. He came from the Berkeleys of Stoke Gifford, a cadet branch of the main Berkeley family, as a descendant of Sir Maurice de Berkeley