He served in the Union (Northern) navy under Farragut during the American Civil War. He was granted naval command of the Pacific (1897). His victory over the Spanish fleet at Manila Bay on 1 May 1898 was not only decisive for the outcome of the Spanish-American War but also for the future of US imperialism in the Pacific. In 1899 he made a triumphal progress through New York and was created the first ever US admiral.