He served with the British forces under James Wolfe that participated in the Gulf of St. Lawrence Campaign (1758) and captured Quebec from France in 1759. Dalling was Governor of Jamaica from 1777 to 1782 and commander-in-chief of the forces in Madras (Fort St. George), from 1784 to 1786. He was made a colonel of the 60th Foot in 1776 and, having been promoted to lieutenant-general in the army in 1782, he became colonel in the 37th Foot in 1783. Promoted to full general in 1796, he was created a baronet of Burwood in the County of Surrey on 11 March 1783.