The Caroline Affair
The battle of 1812 was supposedly lost by the U.S. and therefore won by Great Britain. Apparently, it is true. But rebels in Upper and Lower Canada would continue to challenge the Anglo-Anglican Monarchists by waging a secret uprising in both parts of Canada that would end in 1838. In Lower Canada, the hanging of a few French-Canadian rebels at "au Pied-du-Courant" would stop the rebellion while in Upper Canada the revolt would rise to a higher degree of intensity and lead ultimately to a major diplomatic incident between the British, North America and the U.S. It is remembered as the Caroline Affair.
It's impossible not to draw some lines between the Battle of 1812 and the Caroline Affair in 1837-38 despite the lapse of time. The victory roll of 1812 was much used by the Brits to hide the revolt of the Catholics forming the majority of Lower Canada, namely the French, and a strong minority of Upper Canada, mostly from Irish descent. Therefore, the treaty against the Anglican Monarchists was much more from the inside than from the U.S. After 1812 and until the Caroline Affair, forging unity among colonials of different languages and religions was paramount and overwhelming to the political establishment in order to supersede the call for a Republic similar to the U.S., where state and church are separated.
As a matter of fact, the Battle of 1812 settled nothing from the inside. The revolt was still brewing among Catholics whether from French or Irish descent.
In 1837-38, after the many battles waged by the S.S. Caroline, a steamship led by Irish colonial rebels but armed by Americans, in the surroundings of Niagara Falls, the meaning and the strange negotiations preceding the treaty that ensued to end this strange war show a different perspective on the true nature of the U.S.-Canada diplomatic relationship at a sensitive time. The Brits invaded the U.S. soil in order to neutralize the so-called Irish rebels, in other words Catholics were plotting the annexation of British North America to the U.S. The stakes were high, namely living free in a Republic that should be extended to the North, and ending religious segregation and the aristocratic privileges of an English monarchist minority group. But the coup led by amateurs simply failed.
These incidents, quite far and separated from the Battle of 1812, led to the Webster-Ashburton Treaty. During the course of negotiations, U.S. Secretary Webster admitted that the use of force by the Brits was justified considering the necessity of self-defense, which forms the very legal basis of preemptive strike or anticipatory self-defense, but also denied that force was necessary in this particular case. Therefore, the invasion of U.S. territory was not! Lord Ashburton apologized for the invasion.
What conclusion should we draw from this agitated period of Canadian-U.S. relations? British North America was wrong! The Irish Catholic rebels were justified to leave for brighter skies and the Brits should have let them go. Period!
Moreover one Alexander Mcleod, a Canadian sheriff involved in the killing of rebels on U.S. soil, was captured and charged for murder before an American court but finally found innocent on technicalities and repatriated to Canada. McLeod was subject to intense diplomatic correspondance between the two countries.
From this retrospective view, who won the Battle of 1812? The fabric of British North America elite was made of inherited fortune of Anglo-Anglican aristocracy who fixed other people's life by segregation while the American founding fathers were the strongest proponents of the separation of state and church leading the way to equality for all before the law, slavery being a sad exception. Therefore instead of chasing them on foreign soil, the 1837-38 Irish rebels should have been offered a free pass to the U.S. without reprisal like did so many French-Canadians in the aftermath of "au Pied-du-Courant."
As the final result for this whole period, the British won the 1812 Battle but lost the war in the end: the U.S. became the most powerful nation on earth, pressing for the separation of state and faith, while the British North America known has Canada, is still struggling even as of today to avoid breaking up with its French population and threatened by never ending strong regional discrepancies.
References : Avalon Project, Yale University