北西会社
Thomas McKay joined the North West Company after the failure of the Pacific Fur Company in 1813. Between 1815 and 1819 Thomas was in the Red River Colony and fought on the side of the North West Company and the Métis people against the Hudson's Bay Company. McKay fought at the 1816 Battle of Seven Oaks. By 1819 he was back on the Columbia. Within two years the entire North West Company was merged into the Hudson's Bay Company.