The protagonist and anti-heroine of Louise Fitzhugh’s masterpiece Harriet the Spy, first published first in 1964, continues to mesmerize generation after generation of readers. Harriet is an erratic, unsentimental, and endearing prototype–someone very like the woman who dreamed her up, author and artist Louise Fitzhugh.

Born in 1928, Fitzhugh was raised in a wealthy home in segregated Memphis, and she escaped her cloistered world and made a beeline for New York as soon as she could. Her expanded milieu stretched from the lesbian bars of Greenwich Village to the dance clubs of Harlem, on to the resurgent artist studios of post-war New York, France, and Italy. Her circle of friends included artists like Maurice Sendak and playwrights like Lorraine Hansberry.

In the 1960s, Fitzhugh wrote Harriet the Spy, and in doing so she introduced new realism into children’s books-she launched a genre of children’s books that allowed characters to experience authentic feelings and acknowledged topics that were formerly considered taboo. Fitzhugh’s books are full of resistance: to liars, to conformity, to authority, and even (radically, for a children’s author) to make-believe. As a commercial children’s author and lesbian, Fitzhugh often had to disguise the nature of her most intimate relationships. She lived her life as a dissenter–a friend to underdogs, outsiders, and artists–and her masterpiece remains long after her death to influence and provoke new generations of readers.

Harriet is massively influential among girls and women in contemporary culture; she is the missing link between Jo March and Scout Finch, and it’s not surprising that writers have thought of her as a kind of patron saint for misfit writers and unfeminine girls. This lively, rich biography brings Harriet’s creator into the frame, shedding new light on an extraordinary author and her marvelous creation.