British cartoonist Ronald Searle, the creator of the willfully wicked schoolgirls of St. Trinian’s who amused generations of Britons, died Dec. 30 of natural causes in Draguignan, Provence, France. He was 91.

Searle was a prolific illustrator who drew for the New Yorker, Punch and Disney and did title-design and other work for several films, but it was the fictional girls’ boarding school where the students ran riot that most captured the public imagination.

The long-legged, leering schoolgirls drank, smoked and generally cut a swath of destruction; their weapon-wielding antics were colored by Searle’s morbid sense of humor. His satire of the venerable English school system struck a chord, launching a series of hit films, including a 2007 incarnation starring Colin Firth, Gemma Arterton and Russell Brand that has spawned two sequels.

Searle’s secret, as one early profile noted, was to turn “the very epitome of decency and polite tradition for every right-thinking Englishman” into “a place of terror more hellish than anything conceived since the days of Hieronymus Bosch and Pieter Brueghel.”

Searle was born in Cambridge, but his dark streak may have been informed by his experiences as a soldier during WWII: His promising career as cartoonist was interrupted by his capture by the Japanese at Singapore. He spent the rest of the conflict under atrocious conditions as a prisoner of war but managed to keep drawing despite beatings and bouts of malaria and beriberi.

His drawings of camp life were published following his liberation in 1945 in fellow prisoner Russell Braddon’s account of his own captivity, “The Naked Island.”

St. Trinian’s sly schoolgirls made him famous, but Searle long insisted that the students were just “a small part of my work.”

He designed cover art for the New Yorker and a series of editorial cartoons for France’s Le Monde newspaper. He designed wry, occasionally absurd advertisements for Church’s shoes and U.S. Rubber. His Molesworth books, set in the fictional St. Custard’s, also proved popular.

His first work as a designer of film titles was for “The Happiest Days of Your Life” in 1950. Other such credits included bigscreen adaptations “The Belles of St. Trinian’s” (1954) (he also had an uncredited role as a visiting parent), “The Pure Hell of St. Trinian’s” (1960) and “The Great St. Trinian’s Train Robbery” (1966), for which his titles work was uncredited, plus 1965’s “Those Magnificent Men in Their Flying Machines,” Those Daring Young Men in Their Jaunty Jalopies” (1969) and “Scrooge” (1970).

Searle was set designer on the 1955 film “On the Twelfth Day…”; production designer on a pair of films, “Energetically Yours” (1957) and “Dick Deadeye, or Duty Done” (1975); and both set and costume designer on 1963’s “The King’s Breakfast.”

Searle was married twice. His second wife died in July. He is survived by a son and a daughter.