Admiral of the Navy is a rank in the United States Navy that has only been held once in history, by George Dewey. In recognition of his victory at Manila Bay in 1898, United States Congress authorized a single officer to hold the rank of admiral, and promoted Dewey to this rank in March 1899. By a Congressional Act of March 24, 1903, Dewey's rank was established as Admiral of the Navy, effective retroactive to March 1899. The text of the act read as follows:

Be it enacted by the Senate and the House of Representatives of the United States of America in Congress assembled, That the President is hereby authorized to appoint, by selection and promotion, an Admiral of the Navy, who shall not be placed upon the retired list except upon his own application; and whenever such office shall be vacated by death or otherwise the office shall cease to exist.