June 2, 1899: the Malolos Congress declared war on the United States
On June 2, 1899, the First Philippine Republic made a decision that irrevocably altered the trajectory of its struggle for sovereignty: the Malolos Congress officially issued a proclamation declaring war against the United States. While skirmishes and bloody campaigns had already been raging for months, this specific date marks the formal transition from localized resistance to an institutionalized state-level conflict.