Álvarez Jonte joined the Lautaro lodge, founded by Alvear and San Martín, and supported the October 1812 revolution, (started by San Martín after the arrival of the news of the military victory at the Battle of Tucumán). By this movement the First Triumvirate was dissolved and replaced by a Second Triumvirate, formed by Juan José Paso, Nicolás Rodríguez Peña, and Álvarez Jonte. A short while later Paso was replaced by José Julián Pérez, and a few months later, Rodríguez Peña was replaced by Gervasio Posadas, Alvear's uncle.