Henri Gamache was the pseudonym of Anne Fleitman (January 4 1906-October 25 1990), a Jewish author who was active in the United States during the 1940s, and who wrote on the subject of magic.
All of the Gamache books were published in New York City and most of them consist of semi-scholarly popular compilations that draw from (and give credit to) previously-published works on occultism, folklore, and herbalism.
Some researchers took at face value the mid-1950s copyright renewal claims of a book publisher named Joseph W. Kay (a.k.a.
Young is mentioned as a writer of occult books within the pages of the ghost-written autobiography of the famous African American stage magician Benjamin Rucker, better known as Black Herman.
By all accounts, she was a wild, fun-loving, politically liberal woman who strongly supported the Civil Rights Movement.