Born in England, Simcoe was the only of five children to survive past childhood in his family, and lived on to establish a highly accomplished  and successful career. In 1791 the Province of Upper Canada was created under the Constitutional Act of 1791, and Simcoe was appointed the highest rank of Lieutenant Governor. Under this title, Simcoe went on to found modern-day Toronto, and introduced such institutions as the courts, trial by jury, and for abolishing slavery in Upper Canada some 24 years before it was abolished in the British Empire as a whole in 1834.
 

The capital of Upper Canada at this time was Newark, now Niagara-on-the-Lake, considered by Simcoe to be too vulnerable to attack from the nearby Americans. He suggested moving the capital to the more defensible position between both Lake Erie and Lake Huron. In honour of this change he named the new location London, thus founding the present-day city of the same name. Unfortunately, his decision was overruled in favour of Simcoe’s second choice of Toronto.

Thereafter, Simcoe began the construction of two major routes through the province, for both defense and expansion purposes. These two routes would become Yonge Street (the longest street in the world at 1,896) running north-south, and Dundas Street, running east-west. After returning to Britain for heath reasons, Simcoe was appointed commander-in-chief of India but died shortly prior to assuming the position.

Civic Holiday, a statutory holiday celebrated throughout Canada, was established in honour of Simcoe by the Toronto City Council in 1869. Other Ontario municipalities and then other provinces soon took up the holiday as well, leading to its Canada-wide status, but without any attribution to Simcoe himself.