World War II and after

This was interrupted when Benedetto was drafted into the United States Army in 1944 during World War II. He served as a replacement infantryman in the 63rd Infantry Division in France and Germany, moving across France during the winter, then fighting on the front lines in March and April 1945 as the Germans were pushed back across the Rhine. Benedetto narrowly escaped death several times. He would later write, Anybody who thinks that war is romantic obviously hasn't gone through one. At the war's conclusion he was involved in the liberation of a Nazi concentration camp near Landsberg.

Benedetto stayed in Germany as part of the occupying force, but was assigned to an informal Special Services band unit that would entertain nearby American forces. Later, some remarks he made against the Army's racial segregation policies led to his being demoted and reassigned to Graves Registration duties, leading to a further dislike of the military. Subsequently, he sang with the Army military band under the stage name Joe Bari, and played with many musicians who would have post-war careers.

Upon his discharge from the Army and return to the States in 1946, he studied at the American Theater Wing on the GI Bill. He was taught the bel canto singing discipline, which would keep his voice in good shape for his entire career. He continued to perform wherever he could, including while waiting tables. He developed an unusual approach that involved imitating the style and phrasing of other musicians as he sang—such as that of Stan Getz's saxophone and Art Tatum's piano—helping him to improvise as he interpreted a song.

In 1949, Pearl Bailey spotted his talent and asked him to open for her in Greenwich Village. She had invited Bob Hope to the show. Hope decided to bring Bari on the road with him, but suggested he use his real name simplified to Tony Bennett. In 1950, Bennett cut a demo and was signed to Columbia Records by Mitch Miller.