No one really won the War of 1812. Instead everyone just got sick of fighting (the Americans got sick of spending money they didn't have and the British needed to worry more about Napoleon) and said let's act like nothing happened. A lot of people agree that because no one pushed for serious concessions in land or reparations the Treaty of Ghent is one of the main factors that allowed for the close relationship between the American, British, and indirectly, the Canadians for the 200 years following the war. So the running joke is that Canada won, even though Canada didn't even exists because the British retained what then became Canada.
There was one true loser though and that was the Native Americans. Most allied with the British and in the end they basically turned their back on the tribes and let the American do whatever they wanted to the Natives as they pushed west.
