There have been several people named William King:

Canada's First Minister of Labour William Lyon Mackenzie King - Information from Human Resources Development Canada.
CanadaInfo: William Lyon MacKenzie King - Includes a biography, photo and personal stats.
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Gatineau Park and Mackenzie King - Mackenzie King restored a 19th-century farmhouse in Gatineau Park. He settled at The Farm in 1943 and died there in 1950. Site includes a virtual tour.
Meta Description: [ The NCC is a Crown corporation that was created by Parliament in 1959 as the steward of federal lands and buildings in the National Capital Region, with a mandate and mission to build the Capital region into a source of pride and unity for Canadians. La CCN est une société d'État que le Parlement... ]
King - Byng Affair - Letter from William Lyon Mackenzie King to Governor General Byng, 28 June 1926.
King, William Lyon Mackenzie - Article from The Columbia Encyclopedia: Sixth Edition. 2000.
Meta Description: [ King, William Lyon Mackenzie. The Columbia Encyclopedia, Sixth Edition. 2001-05 ]
King, William Lyon Mackenzie. The Mackenzie King Diaries, 1893-1931 - Information on the private diaries of Canada's 11th Prime Minister.
Mackenzie King Images - A series of images of Canada's 10th Prime Minister from the Canadian Heritage Gallery.
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Temperance and The War Speech - A speech entitled Temperance and a Total War Effort given by Prime Minister Mackenzie King on Dec. 16, 1942.
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The Mackenzie King Diary - Online exhibit from the National Archives of Canada.
The Right Honourable William Lyon Mackenzie King - Notes on the 10th Prime Minister's political career.
William Lyon Mackenzie King - Biography and other information about William Lyon Mackenzie King, Canada's Prime Minister from 1921-1926, 1926-1930 and 1935-1948. From First Among Equals website.
William Lyon Mackenzie King - Woodside Home - Waterloo Historical Society's site about King's Woodside home in Berlin (now Kitchener, Ontario).