Mackenzie emigrated from Scotland to York (Toronto) in 1820 and engaged in a lucrative book and drug business, first in York, then in Dundas. In 1823 he moved his family to the beautiful, stately home at the foot of the escarpment at "Queenstown" (Queenston) and opened a country store. A biography of William Lyon Mackenzie can be found at: http://www.biographi.ca/009004-119.01-e.php?BioId=38684

By the 1890's Mackenzie's home had begun to deteriorate. In 1935, the only remnants of the home's former glory were skeletal remains of the walls and a single small stone marker, erected by the Niagara Historical Society, which proclaimed "Home of William Lyon Mackenzie. The birthplace of responsible government, 1823-1824." In 1936, The Niagara Parks Commission undertook the restoration of the Mackenzie House. The beautifully restored home was officially opened on June 18, 1938 by William Lyon Mackenzie King, Prime Minister of Canada, who was the namesake of his grandfather. This site held special significance for King, as it was here that his father proposed to his mother, who was William Lyon Mackenzie's daughter. A gold key was used to officially open the home and was presented to the Prime Minister.