The town was founded in 1649 by Nicolás Hernández, Martín Ángel Toledo and Manuel Salmerón on lands which had been granted to their families earlier in the colonial era. The settlement was officially declared a town in 1889. The early years of the 21st century have been a time of conflict and violence for the municipality. The police commander of the municipality was assassinated in 2003. The events of the
2006 Oaxaca protests have had serious impact on the municipality, In 2006, the municipal palace was taken by
APPO sympathizers who accused the municipal government of serious irregularities and corruption. A general assembly was called and the disavowal of municipal government was approved, replacing it with the “Ayuntamiento Popular de San Antonino Castillo Velasco” (People's City Council of San Antonino Castillo Velasco). This government immediately declared sympathy with APPO and Section 22 of the SNTE teachers’ union. This event divided the residents of the community, A rock smashed the window of the main door of the house of Gonzalo Alonso García, who was recognized by the PRI as the municipal president in 2006, This situation remained until the municipal elections of 2007, which required extra security. Since the early 2000s, there has been a boundary dispute between San Antonino and
Ocotlán de Morelos. At that time, Ocotlán sold an area called “Barratillo de Ocotlán” to San Antonino, but the exact boundaries of the land sold have been in dispute ever since. In 2003, there was a confrontation between the two municipalities over that area, but a more significant one occurred in 2009. The confrontation was sparked by the placement of a sign on
Federal Highway 175 by the
Secretariat of Communication and Transportation and the municipality of San Antonino to indicate the latter's existence to travelers. However, Ocotlán claims the land on which the sign was being erected. The confrontation resulted in injuries to both parties and the use of tear gas by the state police to break it up. The social unrest since 2006 has hurt local craftsmen as tourists and other buyers are scared away by the violence. ==The town and its crafts==