Berkeley represented the senior branch of a family of Saxon origin which had held Berkeley Castle since the middle of the 12th century, and first represented Gloucestershire in 1290. The peerage dates from 1321. Berkeley’s grandfather, the 8th Lord, remained at Westminster during the Civil War, and was nominated to the excise and indemnity commissions, and his father, though a neutral, represented Gloucestershire in 1654 and 1656. In May 1660 he was one of the six peers sent over to invite Charles II to return, but he was not politically active.3Bristol and Glos. Arch. Soc. Trans. i. 131; Cal. Comm. Adv. Money, 695.
Berkeley was recommended to the Gloucester corporation by their high steward, the Marquess of Worcester (Henry Somerset). Though he was under age they eventually ‘agreed to accept the offer’, and he defeated William Cooke at the second general election of 1679. Lord Dursley, as Berkeley was styled after his father’s elevation to an earldom, was moderately active in the second Exclusion Parliament in which he was named to four committees. On 9 Dec. 1680 he was added to a committee for the better regulation of the trials of peers, and to another for searching the papers of two minor figures in the Popish Plot. On 6 Jan. 1681 he was named to the committees for reforming the collection of the hearth-tax and repealing the Corporations Act.4CSP Dom. 1680-1, p. 171, Gloucester Guildhall, council bk. 1656-86, p. 612.
Dursley probably supported exclusion, for Worcester expressed disappointment in his conduct. Lord Berkeley promised amendment when he was re-elected in 1681, but nothing came of this. He was named to no committees at Oxford, but on 26 Mar. he was sent to the Lords to ask for a conference on the loss of the bill of ease for Protestant dissenters. In August, the corporation of Gloucester, now under Tory control, offered Dursley’s seat to Thomas Thynne I and, when this fell through, it was proposed to impose on Dursley a signed undertaking ‘that he will behave himself well to the King in the things in controversy, and be in favour of the opinions they have declared themselves’. There is no evidence that he stood again. His name appears on the list of those opposed to James II and after the Revolution, when he was called up in his father’s barony, he supported the Government. He died of dropsy on 24 Sept. 1710, and was succeeded by his second son, who had represented Gloucester on the Whig interest in the second Parliament of 1701.5CSP Dom. 1680-1, p. 171; Spencer (Althorp) mss, Thynne to Halifax, 13 Aug. 1681; Beaufort mss, Ld. to Lady Worcester, 11 Dec. 1681.