Kohler was a Soviet soldier serving under Irina Spalko and Antonin Dovchenko in 1957.
History
Kohler sat with Marelli and other members of Soviet Special Forces aboard a military convoy on their mission to infiltrate Hangar 51 on American soil.
Behind the scenes
Kohler was uncredited in Indiana Jones and the Kingdom of the Crystal Skull. While it can't made out in the film itself without the Blu-ray edition, Kohler's name tag and the man who played him can prominently be seen standing next to Steven Spielberg on the DVD's special features.