It's a little known fact that the first veterans organization in Canada was not Canadian at all. Instead it was the Grand Army of the Republic, the association of those who fought in the United States Army during the Civil War. As far as I know, veterans of the War of 1812 did not organize this way, if at all. Also, British veterans of imperial wars, everything from Napoleonic Wars through the Crimean War, the Great Rebellion in India, up to Northwest Rebellions in the Canadian west, do not appear to have organized in Canada. The GAR had a significant presence, with eight posts in all, each associated with a US state organization. Four were in Ontario, the William Winer #77 in Hamilton, the Hannibal Hamlin #652 of NY in London, the W. W. Cooke #472 of NY also in Hamilton, and the J. S. Knowlton #532 of NY in Toronto. Quebec had three, the Joseph Bernard #77 of New Hampshire, the General Hancock #73 of Vermont in Montreal, and the Quebec #117 also of Vermont in Quebec City. Winnipeg, far out in the west, had the Manitoba #592 of Pennsylvania. While these constitute just .1% of the 8,000+ GAR branches in the US, and two more abroad in Mexico and Peru, they nonetheless indicate the extent that the Civil War had on North America.
To my knowledge, no research has been done on these posts or the men who belonged to them. Were they Americans who came north or Canadian veterans who returned home? Were any black, or English or French? What about any Confederate veterans since no branches of the UCV existed outside of the United States or even the South? It would be interesting to see how their presence and public role affected the society around them. Nineteenth Century Canada had a strong anti-American sentiment in it. While Civil War veterans spread around the world, they did not organize in the same way as in Canada, Mexico and Peru.