Thomas de Berkeley, 5th Baron Berkeley the inheritance of Berkeley Castle and the other Berkeley lands, as Lisle being heir-general to Thomas de Berkeley, 5th Baron Berkeley and was the Berkeley heir male. Lisle impetuously challenged Berkeley to a battle, and the latter agreed, the battle to be fought the next day at Nibley Green. Lisle was defeated. Thomas de Berkeley, 5th Baron Berkeley Thomas de Berkeley, 5th Baron Berkeley (5 January 1352/53 – 13 July 1417), "The Magnificent", of Berkeley Castle and of Wotton-under-Edge in Gloucestershire, was an English peer and an admiral. His epithet, and that of each previous and subsequent head of his
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