The 3d U.S. Infantry, traditionally known as "The Old Guard," is the oldest active-duty infantry unit in the Army, serving nation since 1784. The Old Guard is the Army's official ceremonial unit and escort to the president, and it also provides security for Washington, D.C., in time of national emergency or civil disturbance. The unit received its unique name from Gen. Winfield Scott during a victory parade at Mexico City in 1847 following its valorous performance in the Mexican War. Fifty campaign streamers attest to the 3d U.S. Infantry Regiment's long history of service, which spans from the Battle of Fallen Timbers to World War II and Vietnam. Since World War II, The Old Guard has served as the official Army Honor Guard and escort to the President. In that capacity, Old Guard soldiers are responsible for conducting military ceremonies at the White House, the Pentagon, national memorials and elsewhere in the nation's capital. In addition, soldiers of The Old Guard maintain a 24-hour vigil at the Tomb of the Unknowns, provide military funeral escorts at Arlington National Cemetery and participate in parades at Fort Myer and Fort Lesley J. McNair.