Philippine Declaration of Independence
Following the end of World War II, the United States granted independence to the Philippines on 4 July 1946 via the Treaty of Manila. July 4 was observed in the Philippines as "Independence Day" until August 4, 1964 when, upon the advice of historians and the urging of nationalists, President Diosdado Macapagal signed into law Republic Act No. 4166 designating June 12 as the country's "Independence Day". June 12 had previously been observed as "Flag Day" and many government buildings are urged to display the Philippine Flag in their offices.
Filipino Repatriation Act of 1935
Along with Guam and Puerto Rico, the United States acquired the Philippines from Spain following the Spanish–American War in 1898 and it became United States territory. The Jones Act of 1916 made it official policy to grant Philippines independence and the Tydings–McDuffie Act of 1935 laid out the timeline and process by which that would happen, with independence fully recognized in ten years. Filipino immigration to the mainland United States started soon after the Philippines became a territory.