The Holland Marsh, considered to be Ontario's "vegetable basket",[2][3] straddles King Township and Bradford West Gwillimbury.

Lieutenant-Governor John Graves Simcoe named King Township for John King (1759–1830),[4][5] an English Under-Secretary of State for Home Office from 1794 to 1801 for the Home Department in the Portland administration when Robert Jenkinson, 2nd Earl of Liverpool was Secretary of State.

[6] Acquisition of the lands for the townships of Etobicoke, King, Vaughan, and York, Upper Canada was completed at a meeting between the Mississaugas and the British at the Credit River on 1 August 1805, where 250,808 acres (1,014.98 km2) were exchanged for £1,700.

[8] By 1801, Timothy Rogers, a Loyalist from Vermont, had travelled the road and found an area on its western boundary immediately southwest of Newmarket very appealing.

More settlers arrived from New York, Pennsylvania, and other Loyalist enclaves over the subsequent years to populate the region, drawn by the abundant, fertile land being apportioned relatively cheaply to newcomers.

[11] The principal villages at the time were Lloydtown, Brownsville (now Schomberg), Bogarttown (now a part of Newmarket), and Tyrwhitt's Mills (now Kettleby).

[12] In 1851, the township annexed from West Gwillimbury the portion of land north of its extant and east of the Holland River as a result of the formation of Simcoe County.

According to a letter by Benjamin Cody to the Newmarket Era published on 7 May 1892, there were church records listing births in the area, and the first white child in King may have been Sarah Rogers, born April 1800.

[17] Some settlements have since been abandoned, or are no longer communities per se, including Bell's Lake, Davis Corners, and King Ridge.

The lyrics allude to the construction of Canada's Wonderland, which is actually located in the City of Vaughan, several kilometres south of the Township of King's southern boundary.

The most significant expenditures for 2007 were general municipal government (27.6%), recreation and culture (21.7%), transportation (17.8%), protection (16.6%) and environmental projects (11.6%).

[22] The Township offices reside at the King City Plaza, a strip mall purchased by the municipal government in the 1990s which also has several business tenants.

[24] In May 2016, the Police Services Board approved the King City substation and announced that a 20-year lease would be executed for use of about 280 square metres (3,000 sq ft) of space in the building.

[25] In June 2016, township staff announced the building would be destroyed in mid-2016 and replaced by a 4,050 square metres (43,600 sq ft) structure on the site at a cost of about $15 million.

The portion of King north of Highway 9 is part of the York—Simcoe electoral district, represented by Scot Davidson of the Conservative Party of Canada.

The remaining areas are part of the King—Vaughan electoral district represented by Anna Roberts of the Conservative Party of Canada.

Previously, King was part of the Oak Ridges—Markham, created for the 2004 election because of rapid growth in York Region,[29] and before that in the Vaughan—King—Aurora electoral district.

The portion of King north of Highway 9 is part of the York—Simcoe electoral district, represented by Caroline Mulroney of the Progressive Conservative Party of Ontario.

[31] The Township of King is located between Toronto and Barrie, stretching from Bathurst Street to just east of Highway 50.

York Region Transit's services are confined to the southeastern area, and GO bus serves the Nobleton and King City communities.

The hamlet of Springhill was established later and flourished; it was renamed King City, now the largest community in the township.