Richard St. John Harris was a two-time Academy Award-nominated and Grammy Award-winning Irish actor, singer-songwriter, producer, director and writer. Larger than life both on and off the screen, highly entertaining on chat shows, especially his very first guest appearance on Michael Parkinson. He appeared on stage and in many films, and is perhaps best known for his roles as King Arthur in Camelot , as Oliver Cromwell in Cromwell and for his portrayal of Albus Dumbledore in Harry Potter and the Sorcerer's Stone and Harry Potter and the Chamber of Secrets , his last film. He also played a British aristocrat and prisoner in A Man Called Horse .