The earl was a staunch Royalist, fighting as Colonel of Foot for Fife and Kinross and in 1648 was involved in an attempt to rescue the King.
He was then sent to the Netherlands to fight for Charles II and was eventually captured at the Battle of Worcester in 1651, after which he spent many years of imprisonment.
After the restoration of the monarchy in 1660 he was appointed governor of the fort and town of Ayr, lieutenant-colonel of the guards and in 1661 he became a member of the Privy Council.
[4] By his first wife he had a daughter Ann, who married Sir Alexander Erskine of Cambo, 2nd Baronet and had issue.
15 September 1673; she wed William Fraser, 5th of Inverallochy and had issue) and Mary, and a son Alexander (bap.