In a Robert Heinlein novel, the War of 1812 is mentioned dismissively as a brushfire conflict on the fringes of the Napoleonic Wars. I'm not sure that the average Briton has any awareness of it at all. But in the US and Canada, the war matters.
In my hometown of Baltimore, the war is very, very personal. When I first moved here, I was surprised to find a Maryland state holiday called Defenders Day on September 12. Say what?
It turns out that September 12 was the land part of the Battle of Baltimore, where the militia stopped the advance of British troops, allowing time to prepare for the naval part of the battle, which was the defense of the city at Fort McHenry.