On June 1, 1812 President Madison and the US Congress declared war on Great Britain and Canada, nominally because the British were kidnapping and forcing American seamen on the high seas to become Royal Navy seamen, along with a few other of such odd issues.
Britain was tied down with Napoleon in Europe, and we knew it. It is hardly ever considered or mentioned that what we really wanted was to annex Canada, which we invaded to that end at least twice during the war, only to be defeated each time, losing the city of Detroit and nearly all of Michigan in the process. Did I mention that in 1812 there were only roughly 6,000 British soldiers defending all of Canada?
Eventually the White House was even burned down.
In any event both sides eventually decided they had enough, and both sides declared that all of their objectives were fully satisfied, and then peace negotiations started in late 1814 and concluded sometime in early 1815.
The bottom line is that this is a war which we started and which can be considered the first humiliating defeat for the USA, as the thinking was that Canada would be an easy pushover, but it beat us in every battle fought there. Perhaps that is why this war is hardly mentioned here, and on June 1, 2012 we did not hold a 200 year celebration of our humiliation.
Come to think of it, did Canada recently celebrate the 200th anniversary of its military victory over the USA?