533Mexico's achievement of political independence from Spain altered the military situation on the northern frontier not at all. The southern Athapascans remained the primary problem of all the frontier provinces. The policy initiated by Viceroy Galvez some thirty-five years before independence had been startlingly successful and the Frontier Provinces had enjoyed their thirty most peaceful and profitable years immediately prior to independence. Yet hostile Apaches remained undefeated, living beyond the frontier forts and posing a threat to the peace of the frontier. Even the bands settled in peace at the military posts still required overawing by the garrison troops, as, well as subsidizing with food, liquor, and clothing rations.
The newly independent Mexicans worried over the threat of geographic expansion by the United States. The Spanish empire had already lost the Floridas to that new nation, and Napoleon had sold the great Louisiana Purchase to it, thus bringing its western boundary into conjunction with the northeastern boundary of New Spain, now Mexico. Mexican officials were aware that the bulk of the area under nominal 534Mexican sovereignty in the direction of the United States was thinly settled by Mexicans if at all, most of it being still the de facto domain of a number of hard-fighting Indian tribes. Therefore frontier officers worried about the possibility of United States attack through this hostile hinterland and infiltration by United States citizens pursuing economic ends such as trapping or trading. The colonial system of frontier forts was hardly altered by independent Mexico, therefore, since the need for border garrisons continued as great as ever.