Nassau District, Upper Canada

The Home District was one of four districts of the Province of Quebec created in 1788 in the western reaches of the Montreal District and partitioned in 1791 to create the new colony of Upper Canada. Known as Nassau District until 1792, it was composed of the areas along western Lake Ontario and Niagara areas or what is now referred to as Central Ontario and the Golden Horseshoe. It was abolished with the adoption of the county system in 1849.

The district was originally bounded to the east by a line running north from the mouth of the Trent River and to the west by a line running north from Long Point on Lake Erie. The district town was originally Newark, later Niagara-on-the-Lake, but became York, Upper Canada, later Toronto, in 1801. In 1798, the district was reorganized to consist of the counties of:

At the same time, the Niagara District was created from:

and the Newcastle District was created from:

Also in 1798, the London District was created from the counties of:

some parts of which were formerly in the Western District.

In 1816, the Gore District was formed from parts of York County and parts of Niagara District.

In 1837, Simcoe County became part of a separate Simcoe District.

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