Truscott's next command came in December 1944. He was promoted to command of the U.S. Fifth Army in Italy when its commander Lieutenant General Mark Clark was made commander of the Allied 15th Army Group, formerly the Allied Armies in Italy (AAI). Truscott led the Fifth Army through the hard winter of 1944–1945, where many of its formations were in exposed positions in the mountains of Italy. He then led the army through the Allied Spring 1945 offensive in Italy culminating in the final destruction of the German forces in Italy.