On April 21, 1898, after the sinking of in Havana Harbor and prior to its declaration of war on April 25, the United States launched a naval blockade of the Spanish colonial 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 Manila. On May 19, Aguinaldo, unofficially allied with the United States, returned to the Philippines and resumed attacks against the Spaniards. By June, the rebels had gained control of nearly all of the Philippines, with the exception of Manila. On June 12, Aguinaldo issued the Philippine Declaration of Independence. Although this signified the end date of the revolution, neither Spain nor the United States recognized Philippine independence.