In 1768, Hamilton became member of parliament for Lancashire and held the seat until 1772 when he was appointed a Steward of the Chiltern Hundreds. In 1799, he inherited his half-nephew's titles and was appointed his successor as Lord Lieutenant of Lanarkshire.
Horse racing
Hamilton was a prominent figure in the world of Thoroughbred horse racing. Between 1786 and 1814 his horses won seven runnings of the St Leger Stakes at Doncaster.[1]
Family
On 25 May 1765, he married Lady Harriet Stewart (a daughter of the 6th Earl of Galloway) and they had five children: