After getting his start writing romance comic books for Charlton, Friedrich was an early recruit to
His best known Marvel work was as the writer and co-creator of Ghost Rider alongside artist Mike Ploog and editor Roy Thomas. He also co-created the character Son of Satan based on a suggestion from Stan Lee.
His credit for co-creating Ghost Rider later became a matter of contention; Friedrich, Ploog, and Marvel's then editor-in-chief Roy Thomas all disagree about who came up with
Following his time at Marvel, Friedrich also wrote for Topps Comics and Atlas/Seaboard Comics before leaving the industry altogether. In 2010, he was honored with the Will Eisner Comic Industry Bill Finger Award for Excellence in Comic Writing.