When was the dominion of Canada formed?

Canada officially became a country on July 1, 1867. The first provinces were Quebec, Ontario, Nova Scotia, and New Brunswick. (The term "Dominion" is simply a historical reference to Section 3 of the British North America Act: "one dominion under the name of Canada". Canada was never known officially as "The Dominion of Canada". It found its way into popular venues such as paper currency and school maps. However, on Canadian bills it was meant as "The Dominion Under Canada" and on school maps as "The Queen's Dominion of Canada".)