He forged an uneasy alliance with Antonio López de Santa Anna, a powerful figure repeatedly in and out of the presidency during this period.

On July 15, 1840, soldiers led by rebellious General José Urrea and Valentín Gómez Farías took the presidential palace and captured President Bustamante, later releasing him.

[1] Shortly thereafter, Mariano Paredes y Arrillaga rose against Bustamante in Guadalajara, Juan N. Álvarez in the south, and López de Santa Anna in Perote, Veracruz.

This time, on September 4, 1841, Valencia joined the rebellion by publishing the Plan de la Ciudadela.

The generals arrayed against him then reached a political agreement proclaimed as the Plan de Tacubaya.

In December 1845 Herrera announced he was setting out at the head of an expedition to repel North American invaders, who had reached Saltillo.

On December 30, 1845, General Valencia, now in charge of the garrison of Mexico City, announced his support for Paredes.

On August 19, 1847, Scott's forces attacked those of Valencia in the town of Contreras, near Mexico City.