Canada-United Kingdom relations (French: Relations entre le Canada et le Royaume-Uni) are the bilateral relations between Canada and the United Kingdom. The two countries have had intimate and frequently-co-operative contact. Both are related by mutual migration, through shared military history, a shared system of government, the English language, the Commonwealth of Nations, and their sharing of the same head of state, Queen Elizabeth II. Despite the shared legacy, the two nations grew apart economically during the 20th century after the U.K. lost its position as Canada's largest trading partner to the United States during the 19th century. However, that trend has been reversed somewhat in the 21st century as the two countries have been negotiating freer trade. Both share a defence agreem