David Ross 12th of Balnagowan signed the National Covenant at Inverness on 26 April 1638. He later joined the royalists for a short time only to become a covenanter again and was present at the defeat of James Graham, 1st Marquess of Montrose at the Battle of Carbisdale in 1650. The Clan Ross and Clan Munro fought on the side of the Scottish Government, then led by the Duke of Argyll. They defeated the royalist army of James Graham, 1st Marquess of Montrose. David Ross, 12th of Balnagowan later led some of the clan at the Battle of Worcester on 3 September 1651 where he was captured and imprisoned at the Tower of London. He is said to have died there in 1653 and been buried in Westminster.