Iberian missionaries spread the cult of San Ildefonso worldwide, including the San Ildefonso Peninsula and municipalities San Ildefonso, Bulacan and San Ildefonso, Ilocos Sur in the Phillippines, San Ildefonso Ixtahuacán in Guatemala, San Ildefonso, San Vicente in El Salavador and San Ildefonso Pueblo, New Mexico.
The original churches of the town were dedicated to Ildefonsus and Saint Dominic .