William Lyon Mackenzie 1795-1861
Born near Dundee, Scotland, William Lyon Mackenzie came to Upper Canada in 1820, and four years later founded a political newspaper, the "Colonial Advocate", at Queenston. Sharply critical of the ruling oligarchy in the province, he entered politics, became leader of the radical wing of the Reform Party, and in 1834 was elected Toronto's first mayor. The rejection of his demands for reform drove him to lead an armed rebellion in Upper Canada in 1837. Defeated by government forces, he escaped to the United States where he found many sympathizers. In 1849 he was permitted to return to Canada and settled in Toronto. Before his death he witnessed the firm establishment of a system of responsible government.
Plaque via Alan L. Brown's site Toronto Plaques. Full page here.