The Philippine Revolution was a conflict waged by the Filipino revolutionaries against the Spanish colonial authorities in an attempt to win the archipelago's independence.
The Philippine Revolution began on August 24, 1896, when the Spanish authorities discovered the Katipunan, an anticolonial secret organization. The Katipunan, led by Andrés Bonifacio, began to influence much of the Philippines, taking full advantage of Spanish failures against Cuban nationalists in 1895 and declaring Spain a weakened empire. During a mass gathering in Caloocan, the leaders of the Katipunan organized into a revolutionary government, named the newly established government "Haring Bayang Katagalugan", and openly declared a nationwide armed revolution. Bonifacio called for an attack on the capital city of Manila. This attack failed; however, the surrounding provinces began to revolt. In particular, rebels in Cavite led by Mariano Álvarez and Baldomero Aguinaldo (who were leaders from two different factions of the Katipunan) won early major victories. A power struggle among the revolutionaries led to a schism among Katipunan leadership followed by Bonifacio's execution in 1897, with command having shifted to Emilio Aguinaldo, who led the newly formed revolutionary government. That year, revolutionaries and the Spanish signed the Pact of Biak-na-Bato, which temporarily reduced hostilities. Filipino revolutionary officers exiled themselves to Hong Kong. However, the hostilities never completely ceased.
On April 21, 1898, after the sinking of the USS Maine in Havana Harbor and prior to its declaration of war on April 25, the United States launched a naval blockade of the Spanish island of Cuba, off its southern coast of the peninsula of Florida. This was the first military action of the Spanish–American War of 1898. On May 1, the U.S. Navy's Asiatic Squadron, under Commodore George Dewey, decisively defeated the Spanish Navy in the Battle of Manila Bay, effectively seizing control of the area surrounding Manila.