In many ways Canadian nationhood was also formed by war. In the wake of the American War of Independence, many thousands of "Empire Loyalists" - Americans who stayed loyal to the crown, flooded north. It was they who made Ontario largely English speaking.

A generation later and the War of 1812, and the attempted American conquest of Canada made the separation more distinct and created a national spirit in Canada. In the war local English speakers fought alongside regular British troops and French Canadians against a common enemy. The French Canadians were very conservative and disliked the revolutionary nature of the US, which they blamed for its exportation to their former mother country.