The United Mexican States is a a federal constitutional republic made up of thirty-one states and one Federal District, the capital city.

During the Great Influenza Epidemic, Mexico took steps to secure its borders against refugees. These measures helped to restrict the spread of the plague south of the border, and the federal government decided to retain the security as the United States collapsed. Although these restrictions have started to loosen, especially in relation to trade, there is some suspicion that Mexico's intentions towards the remnants of the United States is not entirely friendly. There is evidence to suggest that Los Muertos, the bandit group endemic to Arixo, is at least partially supplied by the Mexican armed forces.