The first was the product of an unhappy phase in his life during the Depression when, although he had two degrees, one from the University of Chicago and the other from the London School of Economics, he was out of work and he taught English to immigrants at night school. It was there that he met Kaplan, lately from Poland, who thought he knew English - as he thought he knew everything - but hoped to perfect it, and who tortured the language as readily as he tortured his teachers.
Rosten captured his experience in a succession of short stories which he wrote for the New Yorker under the name Leonard Q. Ross. They reappeared in book form in 1937 as The Education of Hyman Kaplan and were an instant success.
A typical missive from Kaplan read:
Dear Mr Mandelbaum,
Sarah and me want to buy refrigimator. Sarah wants bad. She is saying "Hymie, the eyes-box is terrible. Leeking. Is true." So I answer Sarah by me is OK refrigimator.
Because you are in forniture so I'm writing about. How much will cost refrigimator? Is expensif, mybe by you is more cheap a little. But it must not have short circuit. If your eye falls on a bargain please pick it up.
The book was enjoyed even by the most English of English literati such as P.G. Wodehouse and Evelyn Waugh. The Nurses Association of America asked for a warning wrapper to be put round it because patients who read it were in danger of bursting their stitches. Hyman Kaplan became to America what The Good Soldier Svejk (by Jaroslav Hasek) was to Czechoslovakia.
Some Jews, however, were not amused, and one of them, Nathan Ausbel, an authority on Jewish folklore and Jewish humour, wrote: "Jewish dialect jokes are not Jewish at all, but the confections of anti-Semites who delight in ridiculing and slandering Jews."
The book was in fact an affectionate portrait both of the immigrants and their teachers. Rosten tried to recapture his success in two later volumes, The Return of Hyman Kaplan (1959) and O Kaplan! My Kaplan! (1976), but they did not have the same impact. Most newcomers were by then Hispanic and the joke was lost on them.
Rosten did rather better with The Joys of Yiddish (1968), which was inspired not only by the intrusions of Yiddish words such as "chutzpah" into the American and English language, but by what he called Yinglish, by which he meant English forms of Yiddish expressions such as: "Clever he isn't" or "It's all right by me".
It illustrated, he said, "how beautifully a language reflects the vitality and variety of life itself; and how the special culture of the Jews, their distinctive style of thought, their subtleties of feeling, are reflected in Yiddish, and how this in turn has enriched the English we use today". It too was an instant success.
Rosten was by then established as something of a popular philosopher, with fairly conventional views and a regular column in the now-defunct magazine Look. He also made frequent appearances in the leading American newspapers and on television. In 1971 he wrote an angry polemic, A Trumpet for Reason, against student unrest, and expected a fierce backlash, but didn't receive one, possibly because the unrest was over by the time the book appeared and partly because he had treated a passing phenomenon as a lasting trend.
Rosten was born in Ldz in Poland, and came with his family to the United States in 1911; he grew up in Chicago.
He produced a spate of novels (many of them turned into films, such as Sleep, My Love 1948, and The Dark Corner, 1946), thrillers, screenplays (for films such as The Velvet Touch, 1948) and essays. One book, Hollywood: the movie colony, the movie makers (1941), a sociological examination of the film industry, was all set to become a best-seller, but it was upstaged by Pearl Harbor.
Although Rosten relished popular acclaim he was basically a scholar and taught political science and sociology at Chicago, Columbia, Yale and the New School for Social Research in New York. During the Second World War he was Deputy Director of the Office of War Information in Washington, and in 1945 he became a special consultant to the Secretary of War and was sent on missions to France, Germany and England.
Rosten was an inveterate Anglophile. He had enjoyed his years at the LSE, was amazed by the enthusiastic reception Kaplan had received in the English press, and returned to London whenever opportunity dictated and even when it didn't. He lived in considerable luxury in a penthouse flat in Sutton Place, one of the most exclusive areas of New York, and rented a mews flat in Mayfair. England represented the tranquillity he could not find in America. He loved to rummage in English bookshops and wear English clothes - he contrived to display a subdued elegance - to go to the London theatres and entertain and be entertained in London clubs. He himself was a member of the Savile, the Reform and the Garrick.
Leo Calvin Rosten, author and social scientist: born Ldz, Poland 11 April 1908; married 1935 Priscilla Mead (deceased; one son, two daughters), 1960 Gertrude Zimmerman; died 19 February 1997.