 In contrast to this display of strength of character, he obeyed what he also felt was a "bad order" when he raked a civilian throng with artillery fire after the Mexican authorities failed to surrender Mexico City at the hour demanded by the U.S. forces.The former episode, and later aggressive action against the retreating Mexican army, earned him field promotion to the brevet rank of major.After the war, Jackson was briefly assigned to forts in New York, and then to Florida during the Second Interbellum of the Seminole Wars, during which the Americans were attempting to force the remaining Seminoles to move West.