Jacobite. Educated at Glasgow, Boyd succeeded his father (a government supporter) in 1717 and became a Jacobite, perhaps through the influence of his wife, Lady Anne Livingston.
He was appointed a Privy Counsellor to Prince Charlie Edward Stuart (1720-88) who was entertained at Callendar House by Boyd's wife prior to the Battle of Falkirk, in which Boyd fought. He raised a Cavalry Regiment which supported the Jacobites at Culloden, but the shortage of horses was such that most of them fought on foot.
Boyd was taken prisoner at Culloden and beheaded for treason on Tower Hill (London) on 18th August 1746 and his Earldom was forfeit.
