In December 1917, the 39th was assigned to the 4th Infantry Division and in the spring of 1918, sailed for France as part of the American Expeditionary Force in World War I.

The regiment, less the 3rd Battalion, was affiliated with the Clemson Agricultural College ROTC program and organized on 25 February 1927 as an RAI unit with Regular Army personnel assigned to the ROTC Detachment and Reserve officers commissioned from the program; the 8th Infantry was relieved as Active Associate on 30 June 1927.

The two trees represent the Groves of Cresnes, the site of the regiment's first military success in France during World War I.

The falcon holds an ivy leaf in its bill, in recognition of the shoulder sleeve insignia of the 4th Infantry Division to which the regiment was assigned during World War I.

The motto "D'une Vaillance Admirable" is a quotation from the French citation which awarded the Croix De Guerre with Gilt Star to the regiment for its distinguished service in World War I.

Later in the war, the 39th landed at Utah Beach on 10 June 1944 (D+4) with other reinforcing units and then fought through the rugged French countryside.

The 39th fought through the Battle of the Bulge, helped secure the Remagen bridgehead and moved across Germany as the allied forces finished off the last of the German resistance.

In the war the 39th Regiment received campaign streamers from battles in Algeria, Tunisia, Sicily, Normandy, Northern France, The Rhineland, Ardennes-Alsace, and Central Europe.

The formation was a critical part of the developing NATO force and its capability to deter any Warsaw Pact activity that threatened the integrity of the West German eastern frontier.

In performing this mission, the regiment and its soldiers made a major contribution to assuring the security of Western Europe during this phase of the Cold War.

The regiment participated in Operation Palm Beach, the 1968 Tet Offensive, and the battle of the Plain of Reeds.

[5] The battalions conduct Basic Combat Training, and are part of the 165th Infantry Brigade at Fort Jackson, organized with a headquarters company and six-line (training) companies, designated A through E. For its part in World Wars I, II and the Vietnam War, the 39th Infantry Regiment possesses 21 battle streamers.

Its decorations include four Presidential Unit Citations, four French Croix de Guerre (two with Palm and one with Gilt Star), and the Belgian Fourageré.