"It's about time," Ellington said after the medal was pinned on his jacket Sunday.
Ellington was a gunner aboard a B-17 "Flying Fortress" aircraft when it was damaged by German anti-aircraft fire in 1943. The plane landed in Switzerland, a neutral country obligated to detain Allied troops.
He escaped but arrested by a Swiss border guard, and thus was Ellington a common criminal under Swiss law, and not a prisoner of war in the eyes of the American military.
He was imprisoned in Switzerland's notorious Wauwilermoos prison, run by a commandant who was a Nazi sympathizer, the Milwaukee Journal Sentinel reported Monday.
"It was terrible. We had one bath in five weeks," Ellington recalled. He was released in 1944, escaped a heavily fortified hotel to which he was sent, and returned home. He never applied for POW benefits.
It was the decade-long work of Maj. Dwight Mears, a West Point history professor, which persuaded the Pentagon to give Wauwilermoos internees prisoner-of-war status. Only 12 of the 161 American prisoners are still alive, the newspaper said.
Wearing a U.S. Army Air Corps hat, Ellington's medal was pinned on him Sunday by his wife Rose, whom he married in 1945.