 On 3 September, Italy surrendered to the Allied powers. Hoping to occupy as much of the country as possible before the German Army could react, the U.S. Fifth Army prepared to attack Salerno. On 10 September 1943, the division conducted its second landing at Agropoli and Paestum with the 36th Infantry Division, on the southernmost beaches of the attack. Opposing them were elements of the German 29th Panzergrenadier Division and XVI Panzer Corps. Against stiff resistance, the 45th pushed to the Calore River after a week of heavy fighting. The Fifth Army was battered and pushed back by German forces until 20 September, when Allied forces were finally able to break out and establish a more secure beachhead. On 3 November it crossed the Volturno River and took Venafro. The division had great difficulty moving across the rivers and through the mountainous terrain, and the advance was slow. After linking up with the British Eighth Army, which had advanced from the south, the combined force, under the 15th Army Group, was stalled when it reached the Gustav Line. Until 9 January 1944, the division inched forward into the mountains reaching St. Elia, north of Cassino, before moving to a rest area.
