Formed in 1917, when the United States entered World War I, the 1st Infantry Division is the oldest continuously serving division in the US Army. In World War II, the "Big Red One" took part in the Allied invasion of North Africa in November 1942, driving Axis forces from the continent in 1943. In July of that year, 1st Infantry Division forces invaded Italy, landing in Sicily. On D-Day (June 6, 1944), units of the 1st stormed Omaha Beach as part of Operation Overlord, and later moved through Belgium into Germany, capturing the city of Aachen in late October 1944. After taking part in the Battle of the Bulge in Belgium, the "Big Red One" reentered Germany and, on March 15, 1945, crossed the Rhine.
On May 8, 1945, units of the 1st liberated liberated Zwodau and Falkenau an der Eger, both subcamps of the Flossenbürg concentration camp. Both camps were located on territory that today is in the Czech Republic. Zwodau had been set up in 1944 by the SS for the production of air force equipment and housed some 1,200 female prisoners by March 1945. Falkenau housed 60 prisoners. At the time of its liberation, the camp in Zwodau held some 900 to 1,000 starving women prisoners. The 1st Infantry Division procured food from the neighboring areas and provided badly needed medical attention to the survivors.
The 1st Infantry Division was recognized as a liberating unit by the US Army's Center of Military History and the United States Holocaust Memorial Museum in 1993.
Casualty figures for the 1st Infantry Division, European theater of operations:
- Total battle casualties: 15,374
- Total deaths in battle: 3,307
The 1st Infantry Division's nickname, the "Big Red One," originated from the division's insignia, a large red number "1" on a khaki field. This nickname was adopted during World War I, when the 1st was the first American division to arrive in France.