George Monck was a ruthless professional soldier who had begun the civil wars in the Royalist army, but after imprisonment in the Tower of London, negotiated his release in 1647 based on a promise of loyalty to the Parliamentarian cause. During 1653, Monck had taken up a position as a General-at-Sea in the First Dutch War. In the Spring of 1654, however, he returned to Scotland, where he had most experience, to lead the Commonwealth forces there. On his arrival, he was faced with an ongoing Royalist insurrection, Glencairn's Uprising. The two forces met at Dalnaspidal in July, where Monck decisively quashed the rebels.