Throughout the 19th century the Regular U.S. Army was small, and the state militias provided the majority of the troops during the Mexican–American War, the American Civil War, and the Spanish–American War. With the Militia Act of 1903, the militia was more organized and the name "National Guard" recommended. In 1933, federally-recognized state National Guard units were required to join the National Guard of the United States, a reserve component of the U.S. Army; this is the official founding of the present National Guard.