McGill came to Canada from Scotland in 1766 at the age of twenty-two. After ten years as a fur trader, he moved to Montreal and cofounded Todd, McGill & Co. He continued in the fur trade but also encouraged general trade and in later years pioneered the export of goods to Britain. Active in politics, McGill was a magistrate of Montreal and a member of the first parliament of Lower Canada. He also served for many years as a member of the Governor's Executive Council. During the War of 1812 he commanded the militia that defended Montreal, helping to foil the United States's attempts to annex Canada. Educated at Glasgow University, McGill never lost his love of learning, and his bequest of land and an endowment to found a college bearing his name was a gesture fully consistent with his generous character and strong commitment to the city he had made his own.