American Civil War

With the outbreak of the American Civil War (1861–65), the growing military power of the United States, and increasing tensions between that country and Great Britain, the defence of Canada became an issue of paramount importance for Britain and its North American colonies. Some delegates to the Charlottetown and Quebec City conferences, including John A. Macdonald, believed that the inherent structural weaknesses of the American republic – a frail central government – had made its civil war inevitable.