National Flag Day was first declared on March 6, 1965 to commemorate the date the national emblem was first unfurled after the Philippine Revolutionary Army defeated the Spanish fores in the Battle at Alapan, Imus, Cavite in 1898. On May 23, 1994, Executive Order No. 179 was issued extending the period of celebrating National Flag Day from May 28 to June 12.
On the Flag and Heraldic Code of the Philippines:
