Conversation so far:
What did Gary Cooper do in 1925?
In early 1925, Cooper began his film career in silent pictures.
What pictures did Gary Cooper do?
Sergeant York, High Noon, and The Hanging Tree
Did Gary Cooper win any awards for Sergeant York, High Noon, or The Hanging Tree?
Yes, for all films.
Who did Gary Cooper work with?
Some actors Gary Cooper worked with include Jack Holt, Tom Mix, and Buck Jones.
What was Gary Cooper’s greatest achievement?
Cooper's greatest success was possibly his role as the Cowboy in the film Along Came Jones. The film was one of the top box-office pictures of the year.
What is an important fact about Gary Cooper?
Cooper was one of the founding members of the MPAPAPI, a conservative organization dedicated, to preserving the American way of life and opposing communism and fascism.
Are there any other interesting aspects about this article about Gary Cooper?
Cooper was baptized in the Anglican Church in December 1911 in Britain, and was raised in the Episcopal Church in the United States.

Question: which westerns did he do?
Self-contained rewrite: Which westerns did Gary Cooper do?