Sheffield, John, 1st Duke of Buckingham and Normanby (1648 -1721)
John Sheffield was the only son of Edmund Sheffield, 2nd Earl of Musgrave, and Elizabeth, daughter of Lionel Cranfield, 1st Earl of Middlesex. He succeeded his father in 1658. In 1666 he served as a volunteer in the fleet commanded by Prince Rupert and the Duke of Albermarle, and the next year received the command of a troop of horse. In 1673 he was appointed Colonel of the Old Holland Regiment, and in 1674 he was made a Knight of the Garter. He was in high favour with James II, and was appointed Lord Chamberlain, though he did not become a member of the Church of Rome. In opposition under William and Mary, in 1694 he was created Marquess of Normanby and joined the cabinet, but resumed his opposition in 1696. On her accession, Anne showed him great favour, made him Duke of the County of Buckingham and of Normanby in March 1703 and appointed him Lord Privy Seal, but he was forced to resign in 1705. On the defeat of the Whig Government, he became Lord President of the Council in 1711, but George I removed him from all his offices at his accession. Buckingham married three times, firstly, 18 March 1686, Ursula Stawel; secondly, 12 March 1699, Katherine, daughter of Fulke Greville, 5th Lord Brooke; and thirdly, Catherine, illegitimate daughter of James II and Catherine Sedley. By her he had three sons, one of whom, Edmund, lived to succeed his father as 2nd Duke, but died unmarried in 1735 when all the titles became extinct. Sheffield was the author of several poems and prose pieces, the best of which are his Essay on Poetry and his Essay on Satire.