George Coulouris (October 1, 1903 – April 25, 1989) was a prominent English film and stage actor.

George Coulouris is a British computer scientist and the son of actor George Coulouris. He is Visiting Professor in Residence at University of Cambridge and the author of a textbook in distributed systems. He developed em, the Unix editor, which inspired Bill Joy to write vi.

Son of Greek immigrant father (merchant) and English mother. Educated Manchester Grammar School. George Coulouris was an actor of some force specialising in villains, particularly in his film roles, but quite able for nobler roles. Among the major films he appeared in were Citizen Kane (1941), For Whom the Bell Tolls (1943), 0051754, Papillon (1973) and Murder on the Orient Express (1974). The film which established him as an interesting and reliable heavy, with his massive shoulders and hooded eyes, was Watch on the Rhine (1943). However, he had worked in Hollywood before that through his meeting with Orson Welles. Coulouris studied with Elsie Fogerty at London's Central School of Speech and Drama. His London debut came in 1925 with 'Henry V' at the Old Vic. He was soon playing the yank at the first British staging of Eugene O'Neill's 'The Hairy Ape'. By 1929 he had reached Broadway, via a modern dress version of 'Measure for Measure'; his stage part as Tallant in the 'The Late Christopher Bean' took him to Hollywood in 1933 for MGM's version. The next milestone in his burgeoning career occurred when he was playing a piece called 'Ten Million Ghosts' and met an actor called Orson Welles. They got on well and he joined the Welles' Mercury Theatre, playing 'Mark Anthony' in the famous modern dress production of 'Julius Caesar' (1937). When Welles went to Hollywood to make Citizen Kane (1941), Coulouris climbed into movie history in the part of Walter Parks Thatcher. By that time his future as a cinema actor was assured and he went on to play character parts in a long string of Hollywood productions throughout the 1940s. At the end of the 1940s Coulouris returned to line in England, joining the Bristol Old Vic where he was notable as Tartuffe, transferring to London. In the '50s and '60s George remained a stalwart stage actor in spite of his movie reputation. He liked nothing better than to grapple with Ibsen, Shaw, Strindberg, Moliere or Shakespeare. During these years he tackled Dr. Stockman in Ibsen's 'An Enemy of the People', Patrick Flynn (I) in O'Casey's 'The Plough and the Stars', the father in Sartre's 'Altona', Edgar in Strindberg's 'The Dance of Death' and Big Daddy in Tennessee William's 'Cat on a Hot Tin Roof'. All of these are parts to swell a scene and Coulouris had the flourish to fill them, sometimes to overflowing, always compellingly. In Britain his film parts tended towards the mundane, though he rose to the occasion as the native Babalatchi in Carol Reed's 'An Outcast of the Islands' and seized rare chances to play comedy in 'Doctor in the House' (1953), 'Doctor at Sea' and the Frankie Howard vehicle'The Runaway Bus (1954). Towards the end of his life he tried his hand at writing and produced some charming memoirs describing his early life in Manchester and his early stage experiences, as yet unpublished except for a vivid excerpt published in the Guardian newspaper in February 1986.