Year of the Unicorn

Year of the Unicorn is a 1965 fantasy novel by Andre Norton, in the High Hallack / Witch World series.

Year of the Unicorn is described in wikipedia as "the first time in American publishing history that a young woman was the primary protagonist in a fantasy book, a genre previously thought to be only of interest to boys/men." Arguably, Jirel of Joiry is an earlier protagonist, but not in a novel; Podkayne of Mars is science fiction. Still, this seems unlikely to be quite accurate; for instance, Dorothy in The Wizard of Oz is clearly "the primary protagonist in a fantasy book". So, to the extent true, this must be a fairly specific definition of fantasy: perhaps, trade fantasy aimed at a YA/adult audience?