It was established on 10 April 1979 by the Regional Assembly of the Azores, being based in the National Flag of Portugal used between 1830 and 1910.

By decree of 18 October 1830, the Regency Council established a new National Flag, whose field would be blue and white, with the Portuguese Coat of arms in the middle.

At that time they were however only applied to the national cockade and not to the flag, which remained white with the Portuguese coat of arms in the middle.

The first example of the new blue and white flag was embroidered by Mary II herself and raised for the first time at the Fortress of Angra.

Initially, the new flag was only used at the Azores islands, which were then the only parts of the Portuguese territory controlled by the Liberals.

The name of the archipelago comes from the Portuguese word açor, meaning goshawk, because it was supposed to be a common bird at the time of the discovery.

The shield of Portugal present in the top left corner of the flag represents the Portuguese patriotism of the Azorean people.