The American Civil War was the bloodiest war fought on the continent, with a total of 600,000 dead at war's end in 1865. Canadians were active in the war on both sides: 45,000 fought for the north and a few 1,000 for the south. About 5,000 died in total.
Ontario was the final "station" for the Underground Railroad, bringing runaway slaves to freedom. Josiah Henson, whose life in chains and daring escape in 1830 inspired Harriet Beecher Stowes famed anti-slavery novel "Uncle Tom's Cabin", became a school teacher in Upper Canada. His cabin still stands just SW of Dresden, ON.
To see photos go here: http://www.mountbrydges.ca/dresden2.html
Militant abolitionist, John Brown, often visited Ontario, and planned one of the attacks in the Civil War from nearby Chatham, along with an Upper Canada, black man named Osborn Anderson.
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