The 2nd Infantry Regiment is an infantry regiment in the United States Army that has served for more than two hundred years. It was constituted on 12 April 1808 as the 6th Infantry and consolidated with 4 other regiments in 1815 to form the present unit.

Although the original 2nd Infantry Regiment was constituted in March 1791 and fought in the Northwest Indian War and the War of 1812 at Fort Bowyer in Alabama its history and lineage is not a part of the present regiment. That regiment became part of the 1st Infantry through the consolidations of 1815. For the history about the original 2d Infantry Regiment please refer to the page for the 1st Infantry Regiment

At the end of the War of 1812, an act of Congress dated 3 March 1815 reduced the size of the Regular Army to a maximum of 10,000 men Eight infantry regiments, one rifle regiment and an artillery regiment was formed from the remains of the 46 existing regiments, while the cavalry was eliminated. This was done with no regard for the traditions of the existing regiments. The old regiments which happened to be closest together were pooled to form new regiments and the numbers assigned the regiments were based on the seniority of the colonels commanding them.