Frances Stonor Saunders was born on April 14, 1966, in Windsor, England, west of London. Her father, Donald Slomnicki, moved to England at the end of the war and worked as an investment banker; his family anglicized its name to Saunders. Her mother, Julia (Stonor) Saunders, was a member of one of England’s oldest, aristocratic Roman Catholic families.
Among the notable revelations in her book “Who Paid the Piper?: The C.I.A. and the Cultural Cold War” (1999), the author and documentarian Frances Stonor Saunders showed that the spy agency’s anti-Soviet activities after World War II included producing an animated adaptation of “Animal Farm,” Mr. Orwell’s 1945 satirical fable of the Russian Revolution in which totalitarian pigs rule a barnyard.
“Who Paid the Piper?” documented years of covert efforts by the C.I.A. to manipulate public opinion in Western Europe against communism. Among them was the creation of front organizations like the Congress for Cultural Freedom, which backed magazines and journals like Encounter in Britain and Der Monat in Germany. The agency also sponsored art exhibitions and music tours and funded pro-democracy student activists.
Ms. Stonor Saunders died on Aug. 31 in hospice care in Chichester, in southern England. She was 60 and had lived in London. Her brother Alexander Stonor Saunders said the cause was glioblastoma, an aggressive form of brain cancer.