The following section is a condensation of an article in Wikipedia
The western end of Whitchurch and Markham Townships was purchased by the British crown from the Mississaugas of the New Credit First Nation in 1787 as part of the Toronto Purchase. Whitchurch Township was created in 1792 as one of ten townships in York County. The first European settlements in Whitchurch Township were established in the 1790s, though Whitchurch and large areas of southern Ontario were only ceded by the south-Central Ontario Mississaugas in 1923. Between 1800 and 1802, John Stegman completed a survey of the township which created a system of land concessions. This allowed for the organized distribution of land to settlers, with each concession or block of land containing five, 200-acre (0.81 km2) lots. This layout remains visible today, as the road network in the area reflects the locations of the boundaries between concession blocks.
Early settlers of this period included Quakers and Mennonites or Mennonists--two pacifist groups from the nearby American states of Pennsylvania, Vermont and New York. Both groups were seeking religious freedom, and were identified by the Upper Canadian government as people with necessary skills and abilities for establishing viable communities that could, in turn, attract others to settle in the region. Mercenary German Hessian soldiers, like Stegman, were also granted land in Upper Canada by Britain in exchange for their service in the American Revolution (1774-1784).
Many of the first settlements in Whitchurch Township were developed at the intersections of main roads throughout the township and /or near streams where sawmills could be built to process the timber cleared from the land. The largest urban area was Stouffville, situated on the border between Whitchurch and its southern neighbouring township, Markham. Other communities in the township include Ballantrae, Bethesda, Bloomington, Lemonville, Musselmans Lake, Pine Orchard, Pleasantville, Ringwood, and Wesley Corners.
Ontario GenWeb has a sketchmap of the original townships of York County and York GenWeb provides another sketchmap of the equivalent municipalities in York Region (established 1971). Note that after 1971 the boundaries of the towns of Newmarket, Aurora and Richmond Hill are defined. These towns were all separately incorporated from the townships many years before that date, but none would have had such a large geographical footprint.
The map of York County circa 1951 from Ontario Archives locates the individual municipalities, townships, city, towns and villages of the county. (Click at the bottom of the page to see the map enlarged.)
The primary source for basic documents (vital statistics, land records, wills) for people who lived in the Province of Ontario is the Archives of Ontario, 134 Ian Macdonald Blvd, Toronto, Ontario, Canada M7A 2C5.
Civil registration did not begin in the province until 1869. Before then there may be church records of baptisms and burials. For the most part these are still held by the denomination who recorded them. Copies of marriage records made pre-1869 had to be sent by individual clergymen to the registrar of the county in which the marriage took place. These marriage records are available through Ontario Archives, on micorfilm through LDS libraries, and on paid and unpaid websites, but because they were copied at the registrars' offices, they cannot be considered a primary source.
Vital Records after 1869
Birth, marriage and death registrations are not open to the public until a specific number of years after the event occurred. Births to 1914 are now available [October 2012]; dates for marriages and deaths are later. Birth and death registration was not universally carried out in the early years after its adoption. Deaths were more apt to be reported than births for several years. The more rural the area, the less likely it would be that these happenings were reported to the authorities.
Land Records and Wills
Information on how to access land records and wills is best sought on the Archives of Ontario website. An ancestor's land holding might be found on Canadian County Atlas Digital Project if he was in occupancy circa 1878.
Association for the Preservation of Ontario Land Registry Office Documents (APOLROD). A list of Land Registry Offices for all Counties of Ontario.
The original censuses are in the hands of Library and Archives Canada. All of the original census (1851-1911) images are online with the exception of that for 1861. Not all of them are indexed. Later censuses are not yet available. Census divisions were redrawn as the population increased and more land was inhabited.
E-books and Books