Rainier Wolfcastle is a recurring character in the animated sitcom, The Simpsons. He is a parody of Arnold Schwarzenegger.

He is an action movie star that appeared in the film franchise, McBain and is overly violent in his movies, once having his character throw his boss out of a window.

He is married to Maria Wolfcastle (reference to Maria Shriver) and has a daughter named Greta who had a crush on Bart Simpson.