On September 14, 1847, following the fall of Mexico City, Army units marched into Mexico City as part of a victory parade and review, with the 3d Infantry Regiment leading the procession. As the Regiment passed by the reviewing stand, General Winfield Scott exclaimed to his staff,
“Gentlemen, take off your hats to the Old Guard of the Army.”
The term “Old Guard” was one held in high esteem by students of military history. The term started with Napoleon. Napoleon was said to have hand-picked members of his elite bodyguard and reserve troops, known as the Imperial Guard. Within the Imperial Guard, were three classes of soldiers: the Young Guard, the Middle Guard and the Old Guard. Members of the Old Guard had to be veterans who served under Napoleon from his earliest campaigns (at least three), showed courage in the face of battle and possessed imposing physical traits (usually above-average height).
Though the name was used unofficially since 1847, it was not until 16 August 1963 that the Regiment’s official designation became the “3rd U.S. Infantry Regiment (The Old Guard).”