The first organized resistance against the Japanese invaders that landed in the north in their advance southward to Manila was at Barrios Baroro and Bacsil. The young soldiers, mostly in their twenties, valiantly defended the Baroro Bridge against the advancing enemy forces. Unfortunately, a large number of these young soldiers died in battle as the Japanese forces held the advantage in number, arms, and ammunition.
The civilian populace suffered much among the Japanese occupation, but did not submit themselves to the invaders. Instead, some of them fled to the mountains and joined the underground movement.
AFTER THE WAR
Bacnotan became the provisional seat of the provincial government. San Fernando was then in ruins. As a consequence of this transfer, the La Union High School followed afterwards. The transfer of the provincial high school in Bacnotan resulted in the establishment of the North Provincial High School.
By virtue of RA 2692 sponsored by then Congressman Francisco Ortega, the La Union Agricultural School was established. Nestling cozily at the foot of the mountains in Barangay Sapilang, the 600 hectare agricultural school underwent phenomenal progress and was later named Don Mariano Marcos Memorial State University (DMMMSU).
An attempt was made by the Provincial Board of La Union to create a municipality out of the town of Bacnotan to include Barangay II, Quirino, Ballogo, and Narra. Then President Diosdado Macapagal acted favorably to the proposal by issuing an executive order on November 29, 1965 which provided that the new municipality be created upon the appointment of a mayor, vice-mayor and councilors. However, no appointment of a municipal council was done, hence no new municipality was created.