List of Famous people with last name Castlemaine

Richard Handcock, 2nd Baron Castlemaine, known as Richard Handcock until 1839, was an Irish peer and politician.

Richard Handcock, 4th Baron Castlemaine, styled The Honourable from 1840 to 1869, was an Irish peer.

Richard Handcock, 3rd Baron Castlemaine was an Irish peer and Tory politician.

Roger Palmer, 1st Earl of Castlemaine, PC (1634–1705) was an English courtier, diplomat, and briefly a member of parliament, sitting in the House of Commons of England for part of 1660. He was also a noted Roman Catholic writer. His wife Barbara Villiers was one of Charles II's mistresses.

William Handcock, 1st Viscount Castlemaine, PC (Ire) was an Irish MP and supporter of Union with Great Britain.