Fleur Fenton was born Florence Freidman in New York City (although she often claimed to have been born in Montclair, New Jersey). Her parents were Morris Freidman, a novelty salesman, and his wife, Lena. Her siblings adopted the surname Freeman later in life: Dr. Paul William Freeman, a dentist (1906–1966), and Mildred Freeman Goetze
Fleur Cowles' first husband was Bertram Klapper, a manufacturer of wood shoe heels. They later divorced. Her second husband was Atherton "Pett" Pettingell Jr. (1901–1971), an advertising executive who was a grandnephew of Samuel M. Pettingell, who founded one of the first advertising agencies in America in 1850. They married prior to 1937 and divorced in 1946.
Her third husband was Gardner Cowles Jr. (1903–1982), an heir to the Cowles Media Company, which at one time owned the Des Moines Register and the Minneapolis Star Tribune. Known as Mike, Cowles was the publisher of his family's Look magazine. They married in 1946 and divorced in 1955. She kept his surname professionally.
In the early and mid 1930s, she wrote a weekly column for The New York World-Telegram. In 1937, she became co-founder and executive vice president of the advertising agency Pettingell & Fenton Inc, which later became known as Hartman & Pettingell Inc, then again as Pettingell & Fenton, and finally as Dorland International-Pettingell Fenton Inc.
She founded it with her second husband, Atherton Pettingell, a former executive vice president of Blacker Advertising. Among its clients were A. S. Beck, the shoe concern, Helena Rubenstein, the cosmetics company, and Cohama Fabrics. She resigned from the firm in 1946.
Describing herself as "rough, uncut, [and] vigorous" as her trademark Russian emerald ring, she told Time, "I've worked hard, and I've made a fortune, and I did it in a man's world, but always, ruthlessly, and with a kind of cruel insistence, I have tried to keep feminine". In 1950, she was lampooned by the writer S. J. Perelman in The New Yorker as glamorous editor "Hyacinth Beddoes Laffoon".
In 1947, she became an associate editor at Look magazine, and a year later, an associate editor at Quick magazine. She resigned her position at Look in November 1955 upon her separation from Gardner Cowles and moved to Europe, where she served as the magazine's foreign editorial consultant. Before founding Flair, Cowles was a special consultant to the Famine Emergency Committee in Washington, D.C.
Cowles founded Flair magazine in 1950, and it folded a year later. The magazine, which Time described at its launch as "a fancy bouillabaisse of Vogue, Town & Country, Holiday, etc.," was celebrated not only because of its design and editorial production by European art director Federico Pallavicini (né Federico von Berzeviczy-Pallavicini) but also because of its lavish production. It was the resulting cost of production that killed the magazine, since the expensive special costs (for cover cut-outs for some issues, for example) could not be supported in the long run. This magazine is now sought after by collectors and sells for significant amounts on eBay. Contributors included Saul Steinberg, Salvador Dalí (The Gypsy Angels Of Spain), and many writers and artists who subsequently became well known. The first issue featured Auden, Cocteau, Lucian Freud, Tennessee Williams, Angus Wilson, and many others as contributors.
In later decades, Cowles served on various government committees and represented Dwight D. Eisenhower at the coronation of Elizabeth II. She was a member of the Founding Council of the Rothermere American Institute at Oxford University. In 1996, the book The Best of Flair collected much of the material from the magazine she founded. Her paintings from the books Tiger Flower and Lion and Blue are to be made into three-dimensional computer-animated films.
- Cowles, Fleur "All Too True: Twenty-Nine True Stories That Might Have Been Invented". Quartet Books, Ltd. ISBN 0-7043-2327-3 (0-7043-2327-3)
- Cowles, Fleur "An Artist's Journey". Collins. ISBN 0-00-215083-2 (0-00-215083-2)
- Cowles, Fleur "The Best of Flair". Scriptum Editions. ISBN 1-902686-07-1 (1-902686-07-1)
- Cowles, Fleur "The Best of Flair". Rizzoli Intl Pubns. ISBN 0-8478-2229-X (0-8478-2229-X)
- Cowles, Fleur "The Best of Flair". Harper Collins Canada, Ltd. ISBN 0-06-017390-4 (0-06-017390-4)
- Cowles, Fleur & De Campo, Brooke "Bright Young Things: London". Perseus Distribution Services. ISBN 2-84323-337-2 (2-84323-337-2)
- Cowles, Fleur & Conder, Susan "Flower Decorations : A New Approach to Flower Arranging". Octopus Publishing Group. ISBN 1-85029-028-8 (1-85029-028-8)
- Cowles, Fleur & Conder, Susan "Flower Decorations : A New Approach to Flower Arranging". Random House Publishing Group. ISBN 0-394-54473-0 (0-394-54473-0)
- Cowles, Fleur "The Flower Game" Harper Collins Publishers, Ltd. ISBN 0-00-216625-9 (0-00-216625-9)
- Cowles, Fleur "The Flower Game. W. Morrow. ISBN 0-688-02055-0 (0-688-02055-0)
- Cowles, Fleur "Friends & Memories". Random House. ISBN 0-224-01140-5 (0-224-01140-5)
- Cowles, Fleur "Friends & Memories". Reynal. ISBN 0-688-61200-8 (0-688-61200-8)
- Cowles, Fleur "The Case of Salvador Dali". Heinemann (1959)
- Cowles, Fleur "If I Were an Animal" Morrow. ISBN 0-688-06150-8 (0-688-06150-8)
- Cowles, Fleur "The Life and Times of the Rose". Orion Books Ltd. ISBN 1-85592-533-8 (1-85592-533-8)
- Cowles, Fleur "The Life and Times of the Rose: An Essay on Its History With Many of the Author's Own Paintings". Harper Collins. ISBN 0-688-12082-2 (0-688-12082-2)
- Cowles, Fleur & Vavra, Robert "Lion and Blue". Collins. ISBN 0-00-211495-X (0-00-211495-X)
- Cowles, Fleur & Vavra, Robert "Lion and Blue". Harper Collins. ISBN 0-688-61164-8 (0-688-61164-8)
- Cowles, Fleur & Vavra, Robert "The Love of Tiger Flower" Harper Collins Publishers Ltd. ISBN 0-00-216208-3 (0-00-216208-3)
- Cowles, Fleur & Conder, Susan "The New Guide to Flower Arranging". Octopus Publishing Group. ISBN 1-85029-182-9 (1-85029-182-9)
- Cowles, Fleur "People as Animals". R. Clark. ISBN 0-86072-094-2 (0-86072-094-2)
- Cowles, Fleur & Vavra, Robert "Romany Free". Granite Impex Ltd. ISBN 0-688-61193-1 (0-688-61193-1)
- Cowles, Fleur & Vavra, Robert "Romany Free". Harper Collins Publishers Ltd. ISBN 0-00-216725-5 (0-00-216725-5)
- Cowles, Fleur & Fuentes, Carlos "She Made Friends and Kept Them". Harper Collins Canada, Ltd. ISBN 0-00-255689-8 (0-00-255689-8)
- Cowles, Fleur & Fuentes, Carlos "She Made Friends and Kept Them: An Anecdotal Memoir". Harper Collins Canada. ISBN 0-06-095505-8 (0-06-095505-8)
- Cowles, Fleur & Fuentes, Carlos "She Made Friends and Kept Them: An Anecdotal Memoir". Harper Collins. ISBN 0-06-018713-1 (0-06-018713-1)
- Cowles, Fleur & Vavra, Robert "To Be a Unicorn". Harper Collins Publishers Ltd. ISBN 0-00-217959-8 (0-00-217959-8)
- Cowles, Fleur & Vavra, Robert "To Be a Unicorn". Harper Collins Publishers. ISBN 0-688-06598-8 (0-688-06598-8)
- "Fleur Cowles, 101, Is Dead; Friend of the Elite and the Editor of a Magazine for Them" by Enid Nemy
- Penelope Green, "Mirror, Mirror: Making Life a Bed of Roses", The New York Times, October 10, 1999
- Fleur Cowles profile at Britannica.com
- Paid obit for Dr. Paul W. Freeman, The New York Times, October 4, 1966
- '"Dr. Paul W. Freeman", The New York Times, October 3, 1966
- "News of the Advertising and Marketing Fields", The New York Times, March 16, 1952
- "Mrs Fleur Cowles Remarried in West", The New York Times, November 23, 1955
- "Gardner Cowles Jr. Is Dead at 82; Helped Build Publishing Empire", The New York Times, July 9, 1985
- Fleur Fenton, "New Trend in Furniture Explained", The New York World-Telegram, December 4, 1933
- "Advertising News and Notes", The New York Times, January 7, 1937
- "Advertising News and Notes", The New York Times, November 30, 1938
- "Advertising News and Notes", The New York Times, September 6, 1946
- "Fleur's Flair". Time. September 12, 1949.
- S. J. Perelman, "The Hand That Cradles the Rock", The New Yorker, July 1, 1950
- "Fleur Cowles to Quit", The New York Times, 19 October 1955
- Federico Pallavicini obituary
- "Founding Council | Rothermere American Institute". Rothermere American Institute. Retrieved 2012-11-22.
- "Gleams on the Horizon", The New York Times, 27 August 1939
- "Fleur Cowles Today", The New York Times, by Enid Nemy, April 27, 1976
- U.S. Library of Congress