The San Fernando High School, the given name of La Union High School when it opened its doors on January 19, 1903 to fifty-five students, was the first secondary school established in La Union during the administration of Senor Joaquin Ortega, the first civil governor of the province. Classes then were held in buildings made of stones.

MANGALDAN owns the distinction as the third town in Pangasinan to be founded by the Dominican missionaries. As early as 1591, it already existed as a Spanish encomienda. Its foundation as a town is attributed to Blessed Juan Martinez de Santo Domingo who died a martyr's death in Japan on March 19, 1618.