The corps found in 2016 that a private first class, Harold Schultz, was one of the six men in the photograph. It also determined that a Navy hospital corpsman, John Bradley, whose son wrote a best-selling book about his father’s role in the flag-raising that was made into a movie directed by Clint Eastwood, was not in the image.
The corps began investigating the photograph again in July 2018 after a trio of researchers — Stephen Foley, Dustin Spence and Brent Westemeyer — unearthed new photographs and film footage of the scene atop Mount Suribachi on Iwo Jima.
Photographs showed the patterns of Corporal Keller’s fatigues matching those of one of the flag raisers. It also showed that he, like the man raising the flag, was holding a cigarette, Mr. Spence said.
“It’s like a court case,” Mr. Spence said. “You’re putting together evidence. If I was a prosecutor, a lawyer, that’s what I’m presenting. That’s our case.”
Kay Maurer, Corporal Keller’s daughter, who lives in Clarence, Iowa, said in an interview on Wednesday night that the corps told her last year that they were looking into the possibility that her father, who died in 1979, was in the picture. The corps told her they had used facial recognition technology and had enlisted the Army’s help to verify the researchers’ findings.
Last month, the corps called again with the news that her father was, in fact, in the photograph, Ms. Maurer said. She said that her father rarely discussed the war, probably because many of his friends died or were injured in it.
She said she felt proud to learn that her father had raised the flag, but also “heartbreak that he didn’t feel he could share that with us.”