they entered a 7500 dollar award detective story contest
co-sponsored by McClure's Magazine and Lippincott's publishing house (Frederick A. Stokes company). McClure offered 5000 dollar for the serial rights to the manuscript and the publishing co. put in the 2500 dollar for the hardcover rights. When the time came to choose their detective they took some time thinking it over. What they wanted was "..a name, which, once heard, read or seen in print would have a mnemonic value and remain in the person's memory..." (Dannay in Dick Cavett Show, 1978). Somewhat unusual, easy to remember and which sounded well. After considering James Griffen and Wilbur See, they turned to Dannay's Elmira friend Ellery Herman. The fact that he admired magazine editor Ellery Sedgwick and the poet William Ellery Leonard* was an added bonus. "One night during 1928, during their writing of The Roman Hat Mystery, Fred and Manny were playing cards, probably bridge, when they started looking at the picture cards. Then it hit them. Their brainy sleuth should be christened Ellery King! Before the evening was up, they changed their minds and settled on the Queen." (Patricia Caldwell during 2005 Centenary) "Queen" just sounded well together with "Ellery". The connotation towards homosexuals wasn't seen at the time.
* Leonard, William Ellery (1876-1944), U.S. poet and educator, born in Plainfield, N.J.; professor of English, University of Wisconsin. - Compton Encyclopedia
three months later they called the agent in charge.
They were invited to the Curtis Brown literary agency to see Mr. Rich. There they were told confidentially that they had won with The Roman Hat Mystery, the cousins went to the famous tobacconist Dunhill's and bought each other pipes with the initials EQ on the stem to celebrate. The considerable amount of money would enable them to pack up their families, give up their jobs and go to the south of France. All they have to do was wait of the magazine's decision to be made public any day... It never came. The magazine was taken over by Smart Set and changed course rather drastically. The new publishers with their female readership in mind awarded the prize to Isabel Briggs Myers' Murder yet to come, a writer who is now better known for the Myers-Briggs Personality Test rather than for crime fiction. However Frederick Stokes himself happened to see the manuscript and liked it. So if the cousins agreed to a "phenomenal" advance of 200 dollar a piece Lippincott's still wanted to publish the book and so both Ellery Queens were introduced to the world. They even got them to publish the story ahead of the prize-winner. The book had an "immediate" success. Stokes would go on to release over a dozen "Ellery Queen" publications. The impulsive entry for a detective-story contest; the success of the result, started Ellery Queen on his career.
In the 1929 list of Lippincott's publications The Roman Hat Mystery was a minor title which received little publicity from the publisher. But the cousins hyped their own publication by writing pseudonymous letters to newspapers stating that "Queen" had disclosed dangerous information about tetra ethyl lead found in gasoline to potential murderers. This supposedly even got the attention of the oil-industry itself which started to look in on the problem. The book sold 8000 copies which in itself was a tremendous success. But they stuck with their secure jobs thinking it unwise to start a writing-career on the merits of just one single success. So they worked together on a second and third novel during evenings (nights) and weekends. After the publication of those mysteries, in 1931, the success was an obvious pointer, and Dannay and Lee gave up the business careers they had planned and took to writing. Their agents had put it in not to be mistaken language "to shit or get off the pot".
They took turns creating plots and writing stories about the sleuth Queen, giving clues so that readers might solve each case before seeing the answer. Dannay largely plotted the Ellery Queen novels, and the other cousin Manfred Lee, largely wrote them.