“The Crusaders” are characters from the Canadian comic, Three Aces. This particular episode, from issue #53 (1946), appears to have used the Captain Marvel stories by Otto Binder and the C. C. Beck studio as its template. The three Crusaders are in an anachronistic old European-style kingdom, and overhear what they think is a plot against the king. However, unlike Captain Marvel, the Crusaders have no super powers and can’t just holler “Shazam!”
It's too bad the Canadian comics industry could not compete with the Americans after World War II. Maybe the stories are reminiscent of that period’s American comics, often more silly than suspenseful, but they have their own charm. Anyone who is an expert on the Canadian comic book industry would help considerably if they would tell us who drew this.