From 1793 until 1802 Hamilton was on active service in the North Sea, the Mediterranean, African waters, where he took the island of Goree in April 1800, and the West Indies. In November 1801 he was returned in absentia for Dungannon by the Viscount Northland as a stopgap replacement for a son lost at sea. He was recommended to Northland by his third cousin John James Hamilton, 1st Marquess of Abercorn, on whose succession to the peerage he had sat as a substitute for St. Germans in 1790, and who considered but eventually discarded him as a candidate for county Donegal in the 1790s.
On 22 Apr. 1804 Hamilton, who had resumed active service on the renewal of war, was ordered by St. Vincent to attend Parliament to support Addington’s beleaguered administration and given leave of absence for the purpose.
Returned unopposed for the venal borough of Honiton in 1807, he apparently supported the Portland ministry. There was a ludicrous episode on 12 Apr. 1809 when Hamilton was forcibly arrested by an illiterate sheriff’s officer, who had mistaken him for Sir John Charles Hamilton, a bankrupt. On 14 Apr. he made a formal complaint in the House and his captor was committed to Newgate for breach of privilege. In December he returned from sea ‘for leave of absence to attend Parliament’,
Hamilton’s last active command was in Newfoundland. He later lived at Iping, near Midhurst, where he died 14 Sept. 1849.
