Sister Light, Sister Dark has roots in centuries-old fantasy and folk tradition. Nineteenth- and twentieth-century antecedents can be found in the works of Andrew Lang and the Broth ers Grimm, as well as J. R. R. Tolkien who wrote fantasies based upon medieval lore. The novel's break with tradition lies in reversal of the male point of view and depiction of strong female characters. The warrior women, such as Jenna's swordplay teachers Catrona and dark sister Katri, and Jenna herself, have roots in legendary male counterparts.

Yolen's depiction of a society of women has some precedent in the works of speculative-fiction writers Marion Zimmer Bradley and Anne McCaffrey. The particular concept of light and dark sisters arises from the fantasy tradition of symbolic color usage and the maturation theme. In her A Wizard of Earthsea (1968), for example, part of the "Earthsea Trilogy," author Ursula K. Le...