Oona O'Neil was born in Warwick Parish, Bermuda, the daughter of famed American playwright Eugene O'Neill and English-born socialite Agnes Boulton. Oona had a fairly happy childhood, although she rarely saw her busy father. During her teens Oona attended boarding school in New York where she met Gloria Vanderbilt and Carol Marcus, and in 1941 Oona was named one of the most sought-after débutantes of the social season. Oona felt it was only natural that she become an actress, since she was the daughter of a playwright and the granddaughter of James O'Neill, a noted theater actor during the late 19th century.
Oona traveled to Hollywood in 1942, where she met silent film legend Charles Chaplin at the home of her agent. Chaplin began courting Oona after she auditioned for a film he was directing, and the pair married in 1943. He was 54; she was just 18. Oona scrapped plans to become an actress, opting instead to raise a family of what would be eight children with Charlie. Although Oona was content with her life, she was deeply troubled by the failed relationship with her father, who disowned her and cut communication with Oona when she married Chaplin.
During the height of McCarthyism 1952, Chaplin sailed to England to promote a film. En route, Chaplin learned that he would not be allowed to return to the U.S. unless he would submit to inquires regarding his morality. Refusing to do so, he and his family eventually ended up in Vevey, Switzerland.
Oona spent the rest of her life in Vevey, leaving only a few times after Charlie died in 1977 at the age of 88. (Oona was only 51.) Oona developed a few close relationships with Hollywood icons, like actor Ryan O'Neal, but she never married again. She died in Vevey from pancreatic cancer on September 27th, 1991.