The office began in the 16th and 17th centuries with the Crown-appointed governors of the French colony of Canada followed by the British governors of Canada in the 18th and 19th centuries. Subsequently, the office is, along with the Crown, the oldest continuous institution in Canada. The present incarnation of the office emerged with Canadian Confederation and the passing of the British North America Act, 1867, which defines the role of the governor general as "carrying on the Government of Canada on behalf and in the Name of the Queen, by whatever Title he is designated". Although the post initially still represented the government of the United Kingdom (that is, the monarch in his British council), the office was gradually Canadianized until, with the passage of the Statute of Westminster in 1931 and the establishment of a separate and uniquely Canadian monarchy, the governor general become the direct personal representative of the independently and uniquely Canadian sovereign, the monarch in his Canadian council. Throughout this process of gradually increasing Canadian independence, the role of governor general took on additional responsibilities. For example, in 1904, the Militia Act granted permission for the governor general to use the title of Commander-in-Chief of the Canadian militia, in the name of the sovereign and actual Commander-in-Chief, and in 1927 the first official international visit by a governor general was made. Finally, in 1947, King George VI issued letters patent allowing the viceroy to carry out almost all of the monarch's powers on his or her behalf. As a result, the day-to-day duties of the monarch are carried out by the governor general, although, as a matter of law, the governor general is not in the same constitutional position as the sovereign; the office itself does not independently possess any powers of the Royal Prerogative. In accordance with the Constitution Act, 1982, any constitutional amendment that affects the Crown, including the office of the Governor General, requires the unanimous consent of each provincial legislature as well as the federal parliament.
As governor is the noun in the title, it is pluralized; thus, governors general, rather than governor generals. Moreover, both terms are capitalized when used in the formal title preceding an incumbent's name.