 In 1715, Campbell left the army on being appointed the first deputy Governor of Stirling Castle and held the post until March 1717.He was returned for Argyllshire in the 1715, 1722 and 1727 general elections.He made a second marriage on 21 November 1732 to Anne Callander, the daughter of John Callander, Laird of Craigforth, and widow of Colonel John Blackadder who had succeeded him as Deputy Governor of Stirling Castle.