In 1819, John Scadding, clerk and friend of Lieutenant Governor John Graves Simcoe, established Port Windsor (now Port Whitby), a settlement in the harbour of Windsor Bay on the north shore of Lake Ontario. Since the natural harbour was one of the best along Lake Ontario, Port Windsor thrived and it was not long until the harbour was being used to ship local grain across Canada. The grain from the district was transported to Port Windsor via Brock Street, a plank road that ran north and south from Kingston Road, the main thoroughfare between Toronto and Kingston (now known as Highway 2 or Dundas Street in Whitby).
In 1836, Peter Perry settled at the corner of Highway 2 and Brock Street and opened a wholesale and retail store and a grain business with six branches from Port Windsor north to the Village of Winchester, now known as Brooklin, and Lindsay. Due to Perry’s influence, a large settlement grew up around the four corners, which became known as Perry’s Corners. This area continues to serve as Whitby’s downtown core.
In March 1852, Whitby was chosen as the county town for the newly formed Ontario County, which had been created from the eastern properties of York County. Three years later, on January 20, Whitby – then comprising Port Windsor, Perry’s Corners and Hamer’s Corners, a small settlement to the east of Perry’s Corners – was officially incorporated as a town. Port Windsor was renamed Port Whitby to avoid confusion with the City of Windsor in Essex County.
Development continued in Whitby when the Grand Trunk Railway was constructed in 1856 and a spur line from Port Whitby to Port Perry and Lindsay was added in 1871. With Whitby firmly at the seat of government in Ontario County, construction of the government buildings began in quick succession: the Ontario County Gaol was built in 1853, the County Courthouse was completed in 1854, and the Land Registry building was added later in 1874.When Ontario County was disbanded in favour of the current Region of Durham in 1974, Whitby remained as the location for regional headquarters.