2nd Battalion, 3rd Infantry Regiment

The 2nd Battalion, 3rd Infantry Regiment traces its lineage to when it was first constituted on 3 June 1784 as a company of the First American Regiment and organized on by September 1784 in Pennsylvania or New Jersey. The unit was redesignated on 29 September 1789 as a company of the Regiment of Infantry, on 3 March 1791 as a company of the 1st Infantry, in 1792 as a company of the Infantry of the 1st Sub-Legion, and lastly on 31 October 1796 as a company of the 1st Infantry.

That unit was consolidated between May and October 1815 with a company of the 5th Infantry (first constituted on 12 April 1808), a company of the 17th Infantry (first constituted on 11 January 1812), a company of the 19th Infantry (first constituted on 26 June 1812), and a company of the 28th Infantry (first constituted constituted 29 January 1813) to form a company of the 3rd Infantry Regiment. The resulting unit was designated on 22 May 1816 as Company B, 3rd Infantry. The 3rd Infantry Regiment, the very first American regiment, was first constituted on 3 June 1784 in the regular Army consisting of companies from Connecticut, New York, New Jersey and Pennsylvania.

Company B fought with the Regiment during the Mexican War, and distinguished itself in such significant battles as Palo Alto, Churubusco, and Chapultepec. On the morning of 14 September 1847, it stood with the first units to raise the stars and stripes over the "halls of Montezuma." The Regiment next campaigned in the American West during the Indian Wars, where Company B saw action against the Seminoles, Comanche and the Nez Perce.

When the American Civil War began, the 3rd Regiment was again called into action. As a member of Sykes's Battalion of regulars, the Regiment fought at the First Battle of Bull Run as a part of 1st Brigade, 2nd Division. After distinguishing itself in the first conflict of the war, the 3rd Regiment went on to fight in every major conflict until the war ended. The unit was consolidated on 19 November 1869 with one-half of Company E, 37th Infantry, and consolidated unit was designated as Company B, 3rd Infantry. Company E, 37th Infantry had been first constituted on 3 May 1861 in the Regular Army as Company E, 3d Battalion, 19th Infantry and organized on 7 February 1866 at Newport Barracks, Kentucky. It was reorganized and redesignated on 23 November 1866 as Company E, 37th Infantry. When it was consolidated with Company B and Company E, 3rd Infantry, Company E, 3rd Infantry thereafter had separate lineage.

During the war with Spain, the 3rd Regiment distinguished itself during the Battle of Santiago. At the turn of the century, the 3rd Regiment found itself fighting in the Philippine insurrection. The men of the 3rd Regiment were cited for their valorous actions in the Battles of Malolos, San Isidro and Luzon.

The 3rd Infantry Regiment was assigned on 24 March 1923 to the 7th Division. It was relieved on 15 August 1927 from assignment to the 7th Division and assigned to the 6th Division. It was relieved on 1 October 1933 from assignment to the 6th Division and reassigned back to the 7th Division. It was again relieved on 16 October 1939 from assignment to the 7th Division and reassigned again to the 6th Division. It was relieved 10 May 1941 from assignment to the 6th Division and inactivated on 1 June 1941 at Fort Leonard Wood, Missouri. The unit was reactivated on 14 February 1942 in Newfoundland and inactivated on 20 November 1946 in Germany.

The unit was reactivated 6 April 1948 at Fort Myer, Virginia. On 1 July 1957, B Company was reorganized and redesignated as Headquarters and Headquarters Company, 2nd Battle Group, 3rd Infantry. On 1 June 1966, 2nd Battalion, 3rd Infantry Regiment was activated for the first time at Fort Benning, Georgia. On 1 June 1966, 2-3rd Infantry was assigned to the 199th Light Infantry Brigade and deployed to Vietnam. 2nd Battalion operated in the Bien Hoa Province from 1967 to 1968 and throughout the Long Binh province until 1969. The Battalion was sited for valor for its actions in Saigon-Long Binh and through their actions in both the Tet and Sanctuary counter offensives. The 2nd Battalion, 3rd Infantry was inactivated on 15 October 1970 at Fort Benning, Georgia.

On 15 March 2001, 2-3rd Infantry was reactivated with a new generation of soldiers as a part of the 3rd Stryker Brigade Combat Team, 2nd Infantry Division at Fort Lewis, Washington. 2-3rd Infantry operated at forefront of Army Transformation, as the lead battalion in the interim brigade combat team concept. At the time its total authorized strength was 691 personnel.