during the first days of the revolt of chile against spanish domination in 1810 he was a member of the municipal corporation of santiago, and joined the revolutionary cause with enthusiasm. he began his political career in 1812, when he was elected deputy to the first congress. when, in 1813, general josé miguel carrera marched to meet the invasion of brigadier antonio pareja, the senate appointed a temporary government, and eyzaguirre was elected a member of the junta de gobierno established in march, 1813, along with josé miguel infante and josé ignacio cienfuegos, and which lasted until march 7, 1814.