Cause of death: natural cause
Joan de Beauvoir de Havilland (October 22, 1917 – December 15, 2013), known professionally as Joan Fontaine, was an English-American actress who is best known for her starring roles in Hollywood films during the Golden Age of Hollywood. Fontaine appeared in more than 45 films in a career that spanned five decades. She was the younger sister of actress Olivia de Havilland. Their rivalry was well-documented in the media at the height of Fontaine's career.
She began her film career in 1935, signing a contract with RKO Pictures. Fontaine received her first major role in The Man Who Found Himself (1937) and in Gunga Din (1939). Her career prospects improved greatly after her starring role in Alfred Hitchcock's Rebecca (1940), for which she received her first of three nominations for the Academy Award for Best Actress. The following year, she won that award for her role in Hitchcock's Suspicion (1941). A third nomination came with The Constant Nymph (1943). She appeared mostly in drama films through the 1940s, including Letter from an Unknown Woman and the comedy You Gotta Stay Happy (both 1948), which she co-produced with her second husband William Dozier through their film production company Rampart Productions. In the next decade, after her role in Ivanhoe (1952), her film career began to decline and she moved into stage, radio and television roles. She appeared in fewer films in the 1960s, which included Voyage to the Bottom of the Sea (1961), and her final film role in The Witches (1966), also known as The Devil's Own.
She released an autobiography, No Bed of Roses, in 1978, and continued to act until 1994. Having won an Academy Award for her role in Suspicion, Fontaine is the only actress to have won an Academy Award for acting in a Hitchcock film. She and her sister remain the only siblings to have won lead-acting Academy Awards.
Source : Wikipedia