The 331st Medical Battalion was the organic divisional medical battalion of the 106th Infantry Division. The reports presented here cover the months of December 1944 and January 1945 when the 106th Infantry Division was involved in very heavy fighting in the Ardennes. The German offensive that struck the First U.S. Army on 16 December was heavily concentrated on the newly arrived 106th Infantry Division that had just replaced the 2d Infantry Division on a quiet sector of the front in the Schnee Eifel on the German-Belgian border. German assault units hammered the new division relentlessly and soon the 422d and 423d Infantry Regiments and many of their supporting troops were surrounded. Within days they would surrender as the Germans punched a huge hole in the American lines that soon became the "Bulge."

According to existing doctrine, the three collecting companies of the 331st Medical Battalion, Companies A, B, and C, were aligned in direct support of the 106th's three regiments--the 422d, 423d, and 424th Infantry Regiments, while Company D was the divisional clearing station. Of the battalion's companies, only Company B was largely lost with the surrounded 423d Infantry Regiment that it supported.