<P> The majority of the inhabitants of Upper Canada (Ontario) were Americans, some of them exiled (United Empire Loyalists) and most of them recent immigrants . The Loyalists were extremely hostile to union with the U.S., while the other settlers seem to have been uninterested and remained neutral during the war . The Canadian colonies were thinly populated and only lightly defended by the British Army, and some Americans believed that the many in Upper Canada would rise up and greet an American invading army as liberators . The combination implied an easy conquest . Once the war began retired president Thomas Jefferson warned that the British presence posed a grave threat, pointing to "The infamous intrigues of Great Britain to destroy our government...and with the Indians to Tomahawk our women and children, prove that the cession of Canada, their fulcrum for these Machiavellian levers, must be a sine qua non at a treaty of peace . Jefferson predicted in late 1812, "the acquisition of Canada this year, as far as the neighborhood of Quebec, will be a mere matter of marching, and will give us the experience for the attack on Halifax, the next and final expulsion of England from the American continent ." </P> <P> Maass argued in 2015 that the expansionist theme is a myth that goes against the "relative consensus among experts that the primary U.S. objective was the repeal of British maritime restrictions . He argues that consensus among scholars is that The United States went to war "because six years of economic sanctions had failed to bring Britain to the negotiating table, and threatening the Royal Navy's Canadian supply base was their last hope ." However, he also notes that many historians continue to publish in support of expansionism as a cause, and that even those opposed to the idea continue to include caveats regarding "possible expansionism underlying US motives". Maass agrees that theoretically expansionism might have tempted Americans, but finds that "leaders feared the domestic political consequences of doing so . Notably, what limited expansionism there was focused on sparsely populated western lands rather than the more populous eastern settlements (of Canada)." </P> <P> The long wars between Britain and France (1793--1815) led to repeated complaints by the U.S. that both powers violated America's right as a neutral to trade with both sides . Furthermore, Americans complained loudly that British agents in Canada were supplying munitions to hostile Native American tribes living in United States territory . </P> <P> Starting in the mid-1790s the Royal Navy, short of manpower, began boarding American merchant ships in order to seize American and British sailors from American vessels . Although this policy of impressment was supposed to reclaim only British subjects, the law of Britain and most countries defined nationality by birth whereas the United States allowed individuals who had been resident in America for some time to adopt American citizenship . There were, therefore, large numbers of individuals who were British by British law but American by American law . The confusion was compounded by the refusal of Jefferson and Madison to issue any official citizenship documents: their position was that all persons serving on American ships were to be regarded as US citizens and that no further evidence was required . This stance was motivated by the advice of Albert Gallatin, who had calculated that half of American deep - sea merchant seamen - 9,000 men - were British subjects . Allowing the Royal Navy to reclaim these men would destroy both the US economy and the vital customs revenue of the government . Any sort of accommodation would jeopardize these men, and so concords such as the proposed Monroe - Pinkney Treaty (1806) between the U.S. and Britain were rejected by Jefferson . </P>

What were the causes of war of 1812