The War of 1812 A primary cause of the war of 1812 was the rise of Tecumseh, believed to be backed by the British, caused an urgency for the Americans to expel the British from Canada. The War Hawks, the congress at the time of Madison's presidency, were pushing for the invasion of Canada, and an attack upon the savages who had been tormenting homes on the frontier. Madison never really expected or desired the control of Canada, nor did his colleague Monroe (Secretary of State). He was more or less pushed into the decision. The War of 1812, it is found to be one of most uneconomical wars in the history