 By the time of the Mexican–American War, the Comanches had raided and pillaged large portions of northern Mexico, resulting in sustained impoverishment, political fragmentation, and general frustration at the inability—or unwillingness—of the Mexican government to discipline the Comanches.In addition to Comanche raids, the First Republic's northern border was plagued with attacks on its northern border from the Apache people, who were supplied with guns by American merchants.Goods including guns and shoes were sold to the Apache, the latter being discovered by Mexican forces when they found traditional Apache trails with American shoe prints instead of moccasin prints.