William Berkeley, 1st Earl FitzHardinge refused to claim his right to the earldom. In 1831 William Berkeley was raised to the peerage as Baron Segrave, of Berkeley Castle in the County of Gloucester. Berkeley was returned to parliament as one of two representatives for Gloucestershire in 1810 (succeeding his uncle Sir George Cranfield-Berkeley), a seat he only held until 1811. In 1836 he was appointed Lord-Lieutenant of Gloucestershire, a post he retained until his death. In 1841 he was further honoured when he was made Earl FitzHardinge. Berkeley never married. He had several mistresses, and in 1821 John Waterhouse succeeded in an action for "criminal
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