Following the 1st Duke's execution for his part in the Wars of the Three Kingdoms in 1649, his brother, William, Earl of Lanark, inherited the titles and lands. William died from wounds received at the Battle of Worcester in 1651, whilst leading his regiment into some of the thickest of the fighting. In his will made at the Hague in 1650, he stipulated that the Lady Anne was his heir, over and above his own children, (all daughters, his only son having died in childhood).