It’s positively ubiquitous! According to Gizmodo …
The sound effect that’s been heard in countless movies and TV shows over the decades technically has two birthdays. As a sound itself, it originally debuted in the 1951 film Distant Drums from singer-songwriter Sheb Wooley. But it was officially given its name with the minor character of Private Wilhelm in The Charge at Feather River, a western that came out July 11, 1953. In that movie, Wilhelm (played by actor Ralph Brooks) screams after being shot in the thigh with an arrow, which would come to define its use: in all of its appearances in future media, it would be used when someone got shot, blasted back by an explosion, or fell from a high distance.
Recently, CBS News did a story on the Wilhelm Scream, and the outlet revealed that it managed to find a tape with the first recording session Wooley did for the scream. CalArts researcher Craig Smith explained to CBS that he found the tape among many from the archives of the University of Southern California’s film school that were close to being trashed.