The National Guard, the oldest component of the Armed Forces of the United States and one of the nation's longest-enduring institutions, celebrated its 369th birthday on December 13, 2005. The National Guard traces its history back to the earliest English colonies in North America. Responsible for their own defense, the colonists drew on English military tradition and organized their able-bodied male citizens into militias.

The colonial militias protected their fellow citizens from Indian attack, foreign invaders, and later helped to win the Revolutionary War. Following independence, the authors of the Constitution empowered Congress to "provide for organizing, arming, and disciplining the militia." However, recognizing the militia's state role, the Founding Fathers reserved the appointment of officers and training of the militia to the states. Today's National Guard still remains a dual state-Federal force.

Throughout the 19th century the size of the Regular Army was small, and the militia provided the bulk of the troops during the Mexican War, the early months of the Civil War, and the Spanish-American War. In 1903, important national defense legislation increased the role of the National Guard (as the militia was now called) as a Reserve force for the U.S. Army. In World War I, which the U.S. entered in 1917, the National Guard made up 40% of the U.S. combat divisions in France; in World War II, National Guard units were among the first to deploy overseas and the first to fight.

Following World War II, National Guard aviation units, some of them dating back to World War I, became the Air National Guard, the nation's newest Reserve component. The Guard stood on the frontiers of freedom during the Cold War, sending soldiers and airmen to fight in Korea and to reinforce NATO during the Berlin crisis of 1961-1962. During the Vietnam war, almost 23,000 Army and Air Guardsmen were called up for a year of active duty; some 8,700 were deployed to Vietnam. Over 75,000 Army and Air Guardsmen were called upon to help bring a swift end to Desert Storm in 1991.

Since that time, the National Guard has seen the nature of its Federal mission change, with more frequent call ups in response to crises in Haiti, Bosnia, Kosovo, and the skies over Iraq. Most recently, following the attacks of September 11, 2001, more than 50,000 Guardmembers were called up by both their States and the Federal government to provide security at home and combat terrorism abroad. In the largest and swiftest response to a domestic disaster in history, the Guard deployed more than 50,000 troops in support of the Gulf States following Hurricane Katrina in 2005. Today, tens of thousands of Guardmembers are serving in harm's way in Iraq and Afghanistan, as the National Guard continues its historic dual mission, providing to the states units trained and equipped to protect life and property, while providing to the nation units trained, equipped and ready to defend the United States and its interests, all over the globe.