An illustrated study of the organization, training, tactics, and operations of the US Navy during World War I, both before and after the US formally joined the Entente Powers. In 1914, the US Navy was the third-largest navy in the world. Although World War I brought no opportunity for the type of capital-ship fleet action for which it had been trained, the US Navy carried out (alongside the Allied navies) a wide range of other missions such as patrolling, convoy escort, laying mines, antisubmarine warfare, landing parties, and manning 14in. naval guns ashore on the Western Front, all while pioneering naval aviation against a background of gunboat diplomacy in the "Banana Wars" in the Caribbean. This absorbing new study examines the US Navy's varied activities in the different theaters of World War I, paying particular attention to the considerable array of uniforms, personal equipment, protective clothing, and insignia employed, including those used by the first female US naval personnel. Complementing naval warfare expert Brian Lane Herder's insightful research are archive photographs and eight newly commissioned color plates, providing a detailed and vivid account of the many facets of the US Navy during this pivotal chapter in its history.