O Canada!

Canada Day (French: Fête du Canada) is the national day of Canada, a federal statutory holiday celebrating the anniversary of the July 1, 1867, enactment of the British North America Act, 1867 (today called the Constitution Act, 1867), which united three colonies into a single country called Canada within the British Empire.   Originally called Dominion Day (French: Le Jour de la Confédération), the holiday was renamed in 1982, the year the Canada Act was passed. Canada Day observances take place throughout Canada as well as among Canadians internationally.

Thanks to Wikipedia for the above information.