Chase Nielsen was one of the 80 airmen who, under the leadership of Jimmy Doolittle, disembarked from the U.S.S. Hornet in the first bombing raid over Tokyo in World War II. He was captured by the Japanese following the crash of his bomber and was held as a Prisoner of War until his release after the end of the war in 1945. He was the only Doolittle Raider to return to testify at the War Crimes Trials against the Japanese in January 1946.