World War II: Formation and role

The 1st Infantry Division, known as the “Big Red One”, was one of the first U.S. Army divisions to enter combat in the European Theater during World War II. The division’s shoulder insignia, a red numeral “1,” became one of the most recognizable symbols of the U.S. Army. The division first saw combat during Operation Torch, landing near Oran, Algeria, in November 1942. It subsequently participated in the Tunisian Campaign, contributing to the defeat of Axis forces in North Africa in May 1943. In July 1943, the division took part in the Allied invasion of Sicily, gaining further experience in amphibious and offensive operations.

Early History

Following its pre-war service, the division was reorganized and expanded as part of the United States Army’s mobilization for World War II. The 1st Infantry Division had a long lineage dating back to the First World War, where it established its reputation as a frontline combat formation.

In the early years of the war, the division trained extensively in the United States before deploying overseas. The division departed for overseas service on 1 August 1942 from the New York Port of Embarkation and arrived in Northern Ireland on 6 August 1942, where it began preparations for operations in the European and Mediterranean theaters.

From there, the division participated in Operation Torch in November 1942, followed by combat operations in Tunisia and Sicily, before returning to England to prepare for the invasion of northwest Europe.

Command Chronology (World War II)

Major General Terry de la Mesa Allen Sr. Feb 1942 – Aug 1943
Major General Clarence R. Huebner Aug 1943 – Jul 1945

Order of Battle (World War II)

This technical list represents the core structure of the division during its operations in the European Theater.

Infantry Regiments

• 16th Infantry Regiment
• 18th Infantry Regiment
• 26th Infantry Regiment

Division Artillery

• 5th Field Artillery Battalion
• 7th Field Artillery Battalion
• 32nd Field Artillery Battalion
• 33rd Field Artillery Battalion

Reconnaissance and Support Units

• 1st Reconnaissance Troop (Mechanized)
• 1st Engineer Combat Battalion
• 1st Medical Battalion
• 1st Signal Company

Additional Division Units

• 701st Ordnance Light Maintenance Company
• 1st Quartermaster Company
• Military Police Platoon
• Band

Normandy Campaign

Omaha Beach (6 June 1944)

On 6 June 1944 (D-Day), the division participated in the Allied invasion of Normandy, landing on Omaha Beach alongside the 29th Infantry Division. The division’s assault elements, particularly the 16th Infantry Regiment, landed in sectors heavily defended by German forces, including elements of the 352nd Infantry Division. Units encountered intense machine-gun fire, artillery, and well-prepared defensive positions.

Despite heavy casualties and initial disorganization, elements of the division succeeded in breaching German defenses, securing exits from the beach, and enabling the continued landing of Allied forces. These actions were critical to the establishment of the Normandy beachhead. Elements of the division played a key role in securing the draws and exits at sectors such as Easy Red, enabling the movement of forces off the beach.

In the days following the landings, the division’s 18th and 26th Infantry Regiments came ashore and played key roles in expanding the lodgment area and sustaining the advance inland.

Advance inland and breakout

Following the landings, the division advanced through the bocage terrain, where dense hedgerows, restricted visibility, and narrow roads slowed operations and favored the defense. The division continued offensive operations in the bocage of Normandy and participated in the breakout following Operation Cobra in late July 1944. As German resistance weakened, the division transitioned to more mobile operations and advanced across France.

Continued operations in Northwest Europe (1944–1945)

Following the breakout from Normandy, the division advanced across France and into Belgium as part of the Allied pursuit of German forces. In October 1944, the division played a leading role in the Battle of Aachen, the first German city captured by Allied forces. The battle marked a significant milestone, as Allied forces entered Germany itself and encountered determined urban resistance. The division later took part in defensive operations during the Battle of the Bulge, contributing to the containment of the German counteroffensive.

Final operations in Germany and Czechoslovakia

In early 1945, the division resumed offensive operations, advancing into Germany as part of the broader Allied advance. It crossed the Rhine River and continued operations into central Germany. In the final weeks of the war, the division advanced into Czechoslovakia, where it remained at the time of Germany’s surrender in May 1945.

Operational significance

The 1st Infantry Division’s combat record reflects the full progression of U.S. Army operations in the European Theater:

• Initial engagement: North Africa (Operation Torch)
• Mediterranean operations: Sicily
• Amphibious assault: Omaha Beach, Normandy
• Breakout and pursuit: France and Belgium
• Urban combat: Aachen
• Defensive operations: Ardennes Offensive
• Final advance: Germany and Czechoslovakia

Its role on Omaha Beach was particularly significant, as the success of the Allied landings depended heavily on the ability of assault units to overcome strong German defenses and secure a foothold in Normandy.