I also concur this is a Loyalist button. Americans who volunteers to fight alongside the British regulars during the war. A lot of them at the conclusion of the war in 1783 fled to Canada. The war in the south was pretty much a terrorist campaign, it was very, very nasty. If the button is made of brass, it is a giveaway to the Loyalist use. The American buttons are almost always made of pewter, except for a few officers' buttons made in France.