In mid-1821, after the Independence of Mexico, General Jose Antonio Echavarri intimidated and threatened the Mayor and the City Council to surrender the city of San Luis to the Army of the Three Guarantees of Agustín de Iturbide (Ejercito de las Tres Garantias de Iturbide), who at the time was emperor of Mexico. They submitted to his demand, as there was no way to resist, and thus proclamation of Independence of San Luis Potosí was declared. The first Constitution of San Luis Potosí was then written on October 16, 1826, and this was in effect until 1835 when Congress proclaimed it centralist. At this point, local legislatures disappeared and state governors were appointed by the central government. This situation lasted until the promulgation of the 1857 Constitution.