Harry Potter her publishers to adopt a more gender-neutral pen name in order to appeal to the male members of this age group, fearing that they would not be interested in reading a novel they knew to be written by a woman. She elected to use J. K. Rowling (Joanne Kathleen Rowling), using her grandmother's name as her second name because she has no middle name. "Harry Potter and the Philosopher's Stone" was published by Bloomsbury, the publisher of all "Harry Potter" books in the United Kingdom, on 26 June 1997. It was released in the United States on 1 September 1998
J. K. Rowling working as a researcher and bilingual secretary for Amnesty International when she conceived the idea for the "Harry Potter" series while on a delayed train from Manchester to London in 1990. The seven-year period that followed saw the death of her mother, birth of her first child, divorce from her first husband and relative poverty until the first novel in the series, "Harry Potter and the Philosopher's Stone", was published in 1997. There were six sequels, of which the last, "Harry Potter and the Deathly Hallows", was released in 2007. Since then, Rowling has written five books for adult readers: