In the first stage of the conflict the balance seemed to tilt in favor of the conservatives, who had the support of most of the formal army, but gradually the trend was reversing, until in Calpulalpan, the conservative party played its last card with its best General Miguel Miramon, commanding eight thousand soldiers, thirty guns and some of the most experienced officers such as Leonardo Márquez, Francisco A. Velez, Miguel Negrete and Marcelino Cobos.

His army was formed by the republican guerrillas who had risen against the coup three years ago and, despite not having mostly military education were hardened soldiers in the battlefields.

[2] The next day, despite their numerical inferiority, at 8:00 am Miramón began an attack on the liberal left wing, trying to take advantage of the superiority of their artillery.

At the same time, General Gonzalez Ortega, Leandro Valle and Alatorre advanced to attack conservatives in the rear, in a move that decided the action of arms and the liberal victory.

[3] Thus, the secular and republican state said in Mexican history by subjecting the powerful corporations that influenced decisively in the direction of the country: The Church and the Army.