The Philippine Revolution (1896–1898), called the "Tagalog War" by the Spanish, was an armed military conflict between the people of the Philippines and Spanish colonial authorities. The Philippine Revolution began in August 1896, upon the discovery of the anti-colonial secret organization Katipunan by the Spanish authorities. The Katipunan, led by Andrés Bonifacio, was a secessionist movement and shadow government spread throughout much of the islands whose goal was independence from Spain through armed revolt. In a mass gathering in Caloocan, the Katipunan leaders organized themselves into a revolutionary government and openly declared a nationwide armed revolution. Bonifacio called for a simultaneous coordinated attack on the capital Manila. This attack failed, but the surrounding provinces also rose up in revolt. In particular, rebels in Cavite led by Emilio Aguinaldo won early victories. A power struggle among the revolutionaries led to Bonifacio's execution in 1897, with command shifting to Aguinaldo who led his own revolutionary government. That year, a truce with the Spanish was reached called the Pact of Biak-na-Bato and Aguinaldo was exiled to Hong Kong. Hostilities, though reduced, never actually ceased. On April 21, 1898, the United States began a naval blockade of Cuba, the first military action of the Spanish-American War. On May 1, the U.S. Navy's Asiatic Squadron under Commodore George Dewey decisively defeated the Spanish navy in theBattle of Manila Bay, effectively seizing control of Manila. On May 19, Aguinaldo, unofficially allied with the United States, returned to the Philippines and resumed hostilities against the Spaniards. By June, the rebels had gained control over nearly all of the Philippines with the exception of Manila. On June 12, Aguinaldo issued the Philippine Declaration of Independence and the First Philippine Republic was established. Neither Spain nor the United States recognized Philippine independence. Spanish rule in the islands officially ended with the Treaty of Paris of 1898 which ended the Spanish-American War. In it Spain ceded the Philippines and other territories to the United States. There was an uneasy peace around Manila with the American forces controlling the city and the weaker Philippines forces surrounding them. On February 4, 1899, in the Battle of Manila fighting broke out between the Filipino and American forces, beginning the Philippine-American War, or also known as the Philippines Insurrection Aguinaldo immediately ordered, "[t]hat peace and friendly relations with the Americans be broken and that the latter be treated as enemies". In June 1899, the nascent First Philippine Republic formally declared war against the United States.