John taught acting school at Julliard, and his first graduating class in 1972 included Kevin Kline and Patti LuPone.
John parodied actor Sydney Greenstreet in The Cheap Detective (1978).
John's first film appearance, in which he played a duellist, as well as acting as producer with Orson Welles on, Too Much Johnson (1938), was contained on only one copy owned by Welles, and was destroyed by a fire at Welles' villa in Madrid, Spain in August, 1970.
John appeared in the 1983 ABC TV mini-series, The Winds Of War, as Jewish professor Aaron Jastrow.
John claimed that he had intimate relations with both Olivia De Haviland and her sister, Joan Fontaine.
John was one of the station show production staff during Orson Welles' famous "War Of The Worlds" broadcast on Halloween, 1938.
John published his autobiography, "Unfinished Business," in 1988.
John beat out James Mason for the part of Professor Kingsfield in The Paper Chase (1973).
John was married twice, to Zita Johann from 1929 to 1933, and to Joan Houseman, from 1952 until his deah in 1988.
John wrote the screenplay for Jane Eyre (1944).
John was a spokesperson for Smith & Barney, appearing in a number of company commercials in the 1980s.
John did a Puritan cooking oil television commercial in 1984.
John won the National Board Of Review award for Best Supporting Actor in The Paper Chase (1973).
John was one of the co-founders of the Theatre Group at the University of California at Los Angeles in 1959, with Robert Ryan and Sidney Harmon.
John wrote 3 memoirs of his life; "Run-Through" (1972), "Front And Center" (1979), and "Final Dress" (1983).
John was a member of the jury at the Venice Film Festival in 1962.
John was a producer on Citizen Kane (1941), but left the production after an argument with Orson Welles.
John founded the Mercury Radio Theater with Orson Welles in 1938.
John was nominated for the Best Picture Oscar for Julius Ceasar (1953), which he produced, and won the Best Supporting Actor Oscar for The Paper Chase (1973).
John produced over 20 films, including The Blue Dahlia (1946, with Veronica Lake and Alan Ladd, and Julius Caesar (1953), with Marlon Brando.