Ilocos Sur's history reflects that of the Philippine history in its entirety. In Vigan, the Villa Fernandina founded in 1574 by Juan de Salcedo, grandson of the Adelantado Miguel Lopez de Legaspi, markers and inscriptions can be found throughout the city.

Following the exploration and conquest of the Ilocos by the Castillan sword, the evangelization of the inhabitants was pursued with the characteristic zeal of the Augustinian missionaries. The stone churches built over the centuries reflect Spanish power that held sway in union with the Church. It is thus interesting to read the marker found near the door of the Vigan Cathedral, placed there by the Philippine Historical Committee.