The cause was cancer, said Barry Burnett, the actor's close friend and agent.
Spinetti played multiple roles in "Oh, What a Lovely War," a musical satire about World War I that opened in London in 1963 and brought him a Tony Award in 1965 after moving to Broadway.
His work in the original London production delighted John Lennon and George Harrison, who asked the well-known actor to appear in the Beatles' first film, "A Hard Day's Night" (1964), in which Spinetti gave a memorable performance as a paranoid television director. Later in the 1960s, he was cast as the mad Dr. Foot in "Help!" and as a drill sergeant in "Magical Mystery Tour."
At a London Beatles Day event in 2010, Spinetti said he was included in the cast of "A Hard Day's Night" at Harrison's insistence.
"He said, 'You gotta be in all our films otherwise me mum wouldn't come and see 'em, because she fancies you,' " Spinetti said.
On another occasion, he told how his association with the Beatles disrupted the opening night of "Oh, What a Lovely War."
"I came out on stage and a group of girls at the back screamed, 'Victor Spinetti, aaaah!' " he said in an interview with absoluteelsewhere.net, a website devoted to the Beatles. "They were shouting things like, 'He's touched George!' " He calmed the screamers by promising to answer questions about the Beatles after the show.
"I love the Beatles, they're lovely people," he told the Los Angeles Times in 1968. "They're extraordinary people because they're so ordinary."
Spinetti also co-wrote "The John Lennon Play: In His Own Write" with Adrienne Kenney. Based on the writings of John Lennon, it opened in June 1968 in London.
Vittorio Georgio Andrea Spinetti was born Sept. 2, 1929, in the South Wales mining town of Cwm (pronounced "Coom"). The eldest of six children of a Welsh mother and an Italian father who ran a fish and chips shop, he struggled growing up with mixed parentage.
"I felt like a Jewish comic in an Irish neighborhood in New York. You had to make someone laugh so he wouldn't hit you. You had to fight for a personality," he told The Times. Sometimes humor failed him: Two of his neighbors beat him, causing him to lose hearing in one ear.
After studying at the Royal Welsh College of Music and Drama in Cardiff, he moved to London to develop his acting career.
His more than 30 film roles included the part of Hortensio in "The Taming of the Shrew" (1967) and Mog Edwards in "Under Milk Wood" (1972), which both starred Elizabeth Taylor and Richard Burton. He also played the concierge in "The Return of the Pink Panther" (1975).
Known for his storytelling prowess, he wove tales about Taylor, Burton, Noel Coward, Tennessee Williams and other famous friends into his one-man shows and a memoir, "Upfront" (2006).
His longtime partner, actor Graham Curnow, died in 1997.