By the time period, my first guess would be something to do with the atomic bomb, but I know he's not John von Neumann. I don't know many scientists by their pictures, only by names.
Looks like Oppenheimer at las Alamos, NM during the later part of War 2 where they developed the first atom bomb.
@Craig Swanson J. Robert Oppenheimer, who, following the end of WW-II, became one of the most-known men publicly in the world. Advised the Administration, gave speaking tours, was said to be the second-most known individual after Albert Einstein. His fame and tenure were destroyed by "witch-hunting" promoted and largely-led by Lewis Strauss. Here is how it went: "In September 1953, Strauss, hoping to uncover evidence of Oppenheimer's disloyalty, asked FBI director J. Edgar Hoover to initiate surveillance to track Oppenheimer's movements. Hoover agreed enthusiastically. The tracking uncovered no evidence of disloyalty but that Oppenheimer had lied to Strauss about his reason for taking a trip to Washington (Oppenheimer met a journalist but had told Strauss that he had visited the White House)." Oppenheimer died essentially a broken man. Frank
Is this subtle humor your way of telling me you do not have a clue to his identity. chirotonsor...showing your vast intellect. clue: He usually wore a uniform, rode a horse and fired a gun.
Yes. He looks a little like a young Wild Bill Hickok ? By the way, what is that triangle shaped thing on his shirt, whoever he is? I've never seen that before.