John Osborne called him "the greatest actor since Marlon Brando".
According to Kenneth Tynan in his profile of Williamson, his erratic behavior during the North American tour of "Hamlet" led one cast member to publicly apologize to a Boston audience.
Born at 3:45am-BST
He disliked actress Helen Mirren, with whom he had had an affair, when the two had appeared in a stage production of "Macbeth", and the feeling was mutual. John Boorman, the director of Excalibur (1981), purposefully cast them as rivals "Merlin" and "Morgana", against both of their protests, because he thought their real-life disdain for each other would generate more tension on screen.
He took over the leading role in "Laughter In The Dark" (1969) at short notice when Richard Burton, at the time the highest-paid actor in the world, was fired by director Tony Richardson. It was generally agreed that Williamson, then aged 30, was far too young to play a middle-aged man infatuated by a much younger woman; however, his reviews were mostly laudatory, although the film was critically panned and a box-office flop.
In his auto-biography, dramatist Samuel Beckett described Nicol as "touched by genius".
Is the subject of two prints in the Photographs Collection at London's National Portait Gallery: "Niicol Williamson," by Bill Brandt (bromide print on card mount, 1965) and "Niicol Williamson as Corialanus in 'Corialanus'" by Johnny Dewe-Mathews (bromide print, 1973).
Starred as King Henry VIII in the Broadway Musical, "Rex".
Trained at the Birmingham School of Speech & Drama.
Turned down a six-figure salary to appear as "Enobarbus" in Charlton Heston's film of William Shakespeare's "Antony and Cleopatra", a role eventually played by Eric Porter.
Was a member of the Dundee Repertory Company in the early 1960s.
Was originally supposed to play the Colonel Kane character in William Peter Blatty's The Ninth Configuration (1980), but dropped out at the last minute and was replaced by Stacy Keach.
Was Prime Minister Harold Wilson's favorite "Hamlet". Wilson praised his performance to President Richard Nixon, and Nixon invited Williamson to stage a one-man show at the White House.
Was twice nominated for Tony Awards as Best Actor (Dramatic): in 1966 for John Osborne's "Inadmissible Evidence", a performance he recreated in the film version of the same name, Inadmissible Evidence (1968) and, in 1974, for a revival of "Uncle Vanya". He lost in 1966 to Hal Holbrook (who won for "Mark Twain Tonight") and in 1974 to Michael Moriarty, who won for "Find Your Way Home".
When appearing as the ghost of John Barrymore in Paul Rudnick's "I Hate Hamlet" on Broadway in 1991, Williamson shocked audiences when he periodically broke character and derided his co-star and the play in well-publicized tantrums. The play lasted only 100 performances despite good reviews.
Won the 1974 Drama Desk Award for Outstanding Performance and a Tony Award nomination for playing the title role in Mike Nichols's all-star production of Anton Chekhov's "Uncle Vanya" in the summer of 1973. Other cast members included Julie Christie, George C. Scott (who also was nominated for a Tony), Conrad Bain, Lillian Gish, Barnard Hughes, and Cathleen Nesbitt. Nichols also was nominated for a Tony for Best Director.