Louis Calhern (February 19, 1895 - May 12, 1956) was an American actor. Born in Brooklyn, New York, he played leads in silent films in the 1920s and was able to successfully transition to talkies, as well as starring on the stage. He is remembered for his role as Ambassador Trentino in the Marx Brothers' Duck Soup, but he reached the pinnacle of his career in the early 1950s when he starred in The Asphalt Jungle, The Magnificent Yankee (for which his performance as Oliver Wendell Holmes won him an Academy Award nomination for Best Actor), Julius Caesar and Blackboard Jungle.
Calhern died in Tokyo of a heart attack while filming The Teahouse of the August Moon. He was replaced in his role by Paul Ford.