 In the late eighteenth century, the crown created a standing military to protect its sovereignty over territory and prevent foreign invasions.The royal army and militias became a way for American-born Spaniards ("criollos") to achieve upward mobility when other paths to advancement were blocked by the Spanish crown's preference for Iberian-born Spaniards ("peninsulares") for high civil and ecclesiastical offices.Because of crown policies, Mexico had no tradition of leadership or self-government.