Military garrisons in North America were provisioned with a diet based primarily on domesticates. A relationship between colonial diets and nationality has been an assumed truism, encouraging the belief that colonial diets were static and predetermined by European norms and leading to devaluation of colonists’ adaptability and agency. We challenge that perspective using zooarchaeological data on soldiers’ diets at 49 American fortifications in North America. Statistical comparisons reveal that some sites relied heavily on provisioned livestock, while others did not. Dietary patterns were significantly impacted by accessibility, length of occupation, garrison size, and local infrastructure. This evidence suggests that reliance on wild game was an adaptive response to local environmental and cultural factors influencing the accessibility of preferred domesticates, regardless of nationality.