After serving at the Admiralty, Trevelyan joined the Cabinet as Chief Secretary for Ireland following the murder of Lord Frederick Cavendish. When Gladstone formed his Third Administration Trevelyan became Secretary of State for Scotland, but resigned a month later over Irish Home Rule and joined the Liberal Unionists. Out of parliament following the 1886 election, he re-joined the Liberals and returned to the House of Commons in 1887. From 1892-95 he was again Scottish Secretary. Trevelyan also had a distinguished literary career and his work included biographies of Macaulay and Charles James Fox and a three volume history of the American Revolution. In 1911 he was appointed a member of the Order of Merit.