At the stroke of midnight, four British colonies merged into a self-governing dominion under the British North America Act. John A. Macdonald became the first prime minister of a new federation stretching from the Atlantic toward an eventually transcontinental future. The date became Dominion Day, later renamed Canada Day in 1982, and is marked annually with fireworks in Ottawa and celebrations nationwide.
The confederation was born less from revolutionary fervor than from practical anxiety: fear of American expansionism after the Civil War, railway debts, and a desire among British colonial administrators to consolidate scattered territories. Delegates from the Province of Canada, Nova Scotia, and New Brunswick had hammered out the details at conferences in Charlottetown and Quebec City in 1864, then crossed to London to secure imperial legislation.
John A. Macdonald, a Kingston lawyer with a fondness for drink and a genius for compromise, became the country's first prime minister. The new dominion initially comprised just four provinces along the St. Lawrence and Atlantic coast; British Columbia, Prince Edward Island, and the vast prairie territories would join later, and full legislative independence from Britain would not arrive until the Statute of Westminster in 1931.
For decades the holiday was called Dominion Day, a modest affair overshadowed by American Independence Day three days later. It was renamed Canada Day only in 1982, coinciding with the patriation of the constitution, giving Canadians a clearer, more assertive national celebration.