[2] Arriving in New Spain in 1621, he found the administration in a bad state and immediately took steps to improve the moral standards of the functionaries.

On March 7, 1623, the viceroy ordered work on the drainage system of the Valley of Mexico to cease, because he considered it costly and unlikely to be effective.

This caused animosity between the two, but the final break occurred because of a court case against Melchor Pérez de Veraiz, corregidor of Mexico City.

Archbishop Pérez de la Serna responded with a general interdict, closing all the churches in the capital for some days.

That afternoon Archbishop Pérez, who in the meantime had been allowed to escape, proclaimed Carrillo de Mendoza deposed as viceroy, and nominated Licenciado Pedro Gabiría as captain general.

That night the viceroy, on the point of being killed by the mob, disguised himself as a servant and fled to the church of San Francisco, where he remained, surrounded by guards.

"Although the crown briefly reinstated Gelves before replacing him, the marqués was in effect the first Mexican viceroy overthrown by popular revolt.

"[3] In 1625, Carillo de Mendoza returned to Spain, where he had an audience with King Philip IV and attempted to justify his decisions as viceroy.

Pérez de la Serna continued as archbishop of Mexico until the arrival of the next viceroy, Rodrigo Pacheco, 3rd Marquis of Cerralvo in November, 1624.