Formation of the Mexican State of Aguascalientes by decree of Santa Anna

Background. Revolutionary activities during the Mexican War of Independence were led in the territory that is today the state of Aguascalientes by figures such as Valentín Gómez Farías, Rafael Iriarte, Rafael Vázquez, and Pedro Parga. The territory belonged to Zacatecas, and its residents had wanted to separate from Zacatecas for some time. In May 1835, Santa Anna's Army of Operations defeated the Zacatecan militia after two hours of combat on 12 May, taking almost 3,000 prisoners; having de facto defeated the liberal government of Zacatecas, which had risen against the central government, Santa Anna then passed through Aguascalientes, where he was well received.

The Decree. On May 23, 1835, Santa Anna issued a federal decree ordering the separation of Aguascalientes from Zacatecas. This act was framed as punishment for Zacatecas’s support of the revolution against the central government. The decree reinstated Pedro Garcia Rojas as political boss but did not immediately define Aguascalientes as a state, leaving its specific category undefined.

Later Developments. Confusion persists regarding the exact date of formal separation. While the 1835 decree initiated the split, Aguascalientes was not declared a department until December 10, 1853, by Santa Anna using extraordinary powers. This later decree referenced earlier actions but did not explicitly cite the March 23, 1835, order, highlighting the complex legal history of the state’s formation.