Upper Canada. Adjutant General's Office : The first Militia Act for Upper Canada, passed in 1793 (33 Geo. III ch. 1), called for the appointment of County Lieutenants, who, in turn, had the authority to appoint officers in their county, subject to the approval of the Lieutenant-Governor. All males between the ages of 16 and 50 were enrolled as militiamen and were called out once a year. In addition, captains of the militia were authorized to call out their companies not less than twice a year to "inspect their arms and instruct them in their duties". The militia in each county was formed into a regiment of five to ten companies. In counties with smaller populations, the militia was formed into battalions, each consisting of five to eight companies, and in the counties too small to support these formations, the militia formed into independent companies.
Although the Militia Act of 1808 (48 Geo. III, ch. 1) extended the maximum age to 60, it declared that "no person above the age of fifty years shall be called upon to bear arms, except on the day of annual meeting, or in time of war or emergency." For the first time, there was provision for the formation of troops of cavalry. An 1812 amendment extended the provisions of the 1808 Act. It called for the formation by each battalion of militia of two flank companies, each composed of one hundred men who could be ordered by the lieutenant governor "to march to any part of this province, upon any such duty as he shall think necessary". The flank companies could be called out for exercise and training for six days in each month and the Act repealed the section of the 1808 Act which limited the period of actual service to six months. Upon these flank companies, in which some two thousand men were registered, fell the brunt of active service during the War of 1812.
A new Militia Act in 1838 (1 Vic. ch. 8) had shortcomings and was superseded by an act of 1839 (2 Vic. ch. 9), by which all male inhabitants of the province between the ages of eighteen and sixty, unless otherwise exempted, were members of the militia and were required to enrol at the annual muster, held each June 4. The militia was still organized on a county basis but there was provision for the Lieutenant Governor to authorize, "in his discretion", regiments or battalions of dragoons, artillery and light infantry as well as rifle companies, a provincial navy and volunteer companies of a provincial marine. Each regiment of militia included a second battalion, composed of officers, "incapable of actual service by reason of old age, infirmity or otherwise" and men between the ages of 50 and 60.
From the end of the 18th century to the unification of Lower and Upper Canada, the role of Adjutant-General was considered the most important position in the Canadian militia. He reported to the Governor General and his principal function was to enforce the various militia acts. As intermediary between the Governor and the militia officers, the Adjutant General was responsible to ensure that the militia assembled and trained annually, that returns and nominal rolls were produced regularly, that general orders were issued and transmitted, that the militia played its part in times of war, and finally, that militiamen and veterans were rewarded for their participation in armed conflicts.
The Militia Act of 1846 (9 Vic. Ch. 28), the first for the United Province of Canada, superseded the existing organizations for Upper and Lower Canada.
The Adjutants General of Militia for Upper Canada were Lieutenant-Colonel Hugh McDonell, June 1794 - December 1807; Lieutenant-Colonel Aeneas Shaw, December 1807 - February 1814 (Colonel 1808, Major-General 1811); Lieutenant-Colonel Colley Lyons Lucas Foster, February 1814 - March 1815; Lieutenant-Colonel Nathaniel Coffin, March 1815 - December 1837 (Colonel 1820); Colonel James Fitzgibbon, 7-8 December 1837 (acting only, but he led the militia against the Mackenzie rebels); and Colonel Richard Bullock, December 1837 - June 1846.