The term "district" was used in the commencement of British rule in Canada to indicate the subdivision of the country, either unorganized and created chiefly for judicial purposes. 

    During the military rule in Canada between the years 1760 and 1764, Canada was divided into the District of Québec, Three Rivers (Trois-Rivières) and Montréal.

    Two years before the commencement of the American Revolution, Sir Guy Carleton, Governor of Québec (1766 - 1778) in the Québec Act of 1774, gave the name "Lancaster" to the upper district referred to as the Western Settlement (1).  It was through his efforts that the American invasion of Canada (1775-1776) was defeated.

    In July 1778 during his second term as governor, Sir Guy Carleton split Lancaster into four districts: Lunenberg, Mecklenberg, Nassau and Hesse.  Three years later Lieutenant Governor John Graves Simcoe anglicized the German names of the districts to Eastern, Midland, Home and Western.

    The advent of the division of these four large districts into counties began in the year 1792!  Lieutenant Governor John Graves Simcoe named the first 19 counties of Upper Canada: Glengary, Stormount, Dundas, Grenville, Leeds, Frontenac, Ontario, Addington, Lennox, Prince Edward, Hastings, Northumberland, Durham, Lincoln, York Suffolk (abolished in 1796 to become part of Middlesex) Kent and Essex.  Other counties were formed at later dates (2).

    In searching for your early Loyalist ancestors, it is wise to look for township, county and district records.  Some of this important information is in the holdings of the county or on microfilms at the  Archives of Ontario , 77 Grenville St, Toronto ON  M7A 2B9.  Please remember that at the turn of the 20th century the two-tiered system of Ontario municipal government of townships and counties changed to a one-tier system of counties.  many township records were deposited within county holdings. 

 To ease your task of Loyalist ancestral hunting in the maze of districts and counties, I've listed the early Ontario counties and the corresponding districts:

County

Part of Which District

  Created in 1792 (merged with Lennox County in 1800)

  Created in 1849

  Created in 1800 (from Dundas and Grenville Counties)

Bathurst, 1824-1838

Dalhousie, 1838-1849

  Created in 1874 (from Grey, Simcoe and Wellington Counties)

  Created in 1792

  Created in 1792

Newcastle, 1802-1849

  Created in 1851 (from Middlesex County)

  Created in 1792

  Created in 1792

  Created in 1792

  Created in 1851 (from Simcoe County)

  Created in 1792

Johnstown, 1798-1849

  Created in 1800 (from Norfolk County)

Talbot, 1845-1849

  Created in 1874

  Created in 1816 (from York County [West Riding])

  Created in 1792

Victoria, 1839-1849

  Created in 1835 (from London District)

Huron, 1841-1849

  Created in 1792

  Created in 1837 (from Kent County)

  Created in 1824 (from Leeds County)

  Created in 1792

Johnstown, 1798-1849

  Created in 1792 (merged with Addington County in 1800)

County

Part of Which District

  Created in 1792

Niagara, 1800-1849

  Created in 1800

  Created in 1792

London, 1798-1837 and Talbot, 1837-1849

  Created in 1792

Newcastle, 1802-1849

  Created in 1792 (Abolished in 1800) Comprised of the islands in the St.Lawrence River

  Created in 1851 (from York County)

  Created in 1800

Brock, 1839-1849

  Created in 1851 (from York County [East Riding])

  Created in 1849

  Created in 1838 (from Durham and Northumberland Counties)

  Created in 1800 (from Glengarry County)

Ottawa, 1816-1849

  Created in 1792

Prince Edward, 1834-1849

  Created in 1845 (from Lanark County)

  Created in 1800 (from Stormont County)

Ottawa, 1816-1849

  Created in 1792

Simcoe, 1843-1849

  Created in 1792

  Created in 1851 (from Peterborough County)

  Created in 1840 (from Halton, Huron and Simcoe Counties)

  Created in 1845 (from Lincoln County)

  Created in 1851 (from Waterloo County)

  Created in 1851 (from Haldimand, Lincoln and York [West Riding] Counties)

  Created in 1792