The independence of the Philippines was officially declared by the US on 4th July 1946, and so this date became the selected date for the celebration of independence across the islands between 1946 and 1961.
However, for many of the indigenous people living in the Philippines, the most important day in terms of the country gaining independence was the day on which it became free from Spanish rule.
As a result, they celebrated its Independence Day on 12th June, which is the anniversary of when Emilio Aguinaldo’s declaration of independence from Spain in 1898. Sadly, this was never recognised by the United States as they acquired the Philippines from the Spanish after the Battle of Manila Bay as part of the Treaty of Paris. As such, they did not consider the islands to be independent on that date.
In spite of this reluctance from the US, on 12th May 1962, Philippine President Macapagal issued Presidential Proclamation No. 28 stating that 12th June would officially be recognised as a public holiday to mark independence from Spain.
Two years later, Republic Act No. 4166 officially changed the date of Independence Day from 4th July to 12th June and renamed 4th July as Philippine Republic Day.
"New independence day". HistoryLearning.com. 2019. Web.