Michigan Territory Michilimackinac, then Detroit; this was essentially a military regime that reported to the governor-general at Quebec. Its role was to supply the needs of the fur traders and discourage any settlements not directly supportive of that effort. After the surrender of Montreal in 1760, British troops under Robert Rogers occupied Detroit and its dependent posts. In 1763, Pontiac's Rebellion saw the fall of Fort Michilimackinac to the northern tribes, and a lengthy siege of Fort Detroit. The siege was lifted in 1764, and rule under a British lieutenant-governor at Detroit followed soon thereafter. Due to the Quebec Act of 1774,
Siege of Fort Pitt become by 1763 and how far British officers were willing to go in ignoring their own soldiers' code of warfare. A devastating smallpox epidemic plagued Native American tribes in the Ohio Valley and Great Lakes area through 1763 and 1764, but the effectiveness of these instances of efforts to spread smallpox remain unknown. After extensive review of surviving documentary evidence, historian Francis Jennings concluded the attempt at biological warfare was "unquestionably effective at Fort Pitt"; Barbara Mann deduced "it is important to note that the smallpox distribution worked"; Howard Peckham noted the resulting fatal epidemic "certainly affected their vigorous prosecution