In the 1937 promotional film "How Walt Disney Cartoons Are Made," an announcer describes some of the intricate work going into the studio's first feature-length film, "Snow White and the Seven Dwarfs," in a department called Inking and Painting.

"Here, hundreds of pretty girls in a comfortable building all their own, well-lighted, air-conditioned throughout, cover the drawings with sheets of transparent celluloid," the announcer says, over images of white-gloved young women preparing male animators' drawings for the screen. "Then they painstakingly trace every line...."

At Disney in the 1930s — as at just about every other workplace in America at the time — female employees had their place, making the creative work of men look good. (It helped if the women looked good, too.)

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Three-quarters of a century later, for the first time on a Disney animated feature, a woman's place is in the director's chair. Jennifer Lee, a screenwriter, shares directing credit on "Frozen" with animator Chris Buck.

At the same time, the Burbank studio is releasing the short film "Get a Horse!," a retro-style Mickey Mouse short directed by Lauren MacMullan of "The Simpsons," marking the first time a woman has had solo directing credit on any Disney Animation movie.

The timing is purely coincidental, according to Disney Animation Chief Creative Officer John Lasseter. But the new era of female creative leadership at the studio is the product of decades of evolution in a slow-moving field popularized by Walt and his "Nine Old Men."

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"Animation has been a male-dominated industry for a long time," Lasseter said. "Not that it's been an old boys' club. There have been real superstars that were women. But now you're seeing more women in supervisory and leadership roles, in story, in layout, in animation; in the production side there's a lot of very strong women. It's been growing."

Both Lee and MacMullan seem discomfited by the attention they're getting for their gender. "Am I really the first woman to do something here by myself?" MacMullan said. "We had to go check because it didn't really occur to us." According to Lee, "It wasn't my top concern in any way."

The recent boom in animated movies — 11 will get a wide theatrical release this year — has meant more opportunity. But animation isn't much different from the wider community of Hollywood when it comes to the gender of directors. Women accounted for 9% of the directors on the top 250 domestic-grossing films in 2012, according to the Center for the Study of Women in Television and Film at San Diego State University.

Essential perspective

Recently Lee, MacMullan and 12 other women who worked on "Frozen" and "Get a Horse!" as animators, story artists, visual development artists and production managers gathered in a conference room at Disney to talk about their roles at the company and impact on their films, as well as on Disney's complicated legacy of female characters.

"These are big animated movies," MacMullan said. "They cost a lot of money, and what everyone wants for their movie is to hit those four quadrants: You want men, women, little boys, little girls, and the best way to make those movies is with women involved in the making of them."

A loose retelling of the Hans Christian Andersen fairy tale "The Snow Queen," "Frozen," which is due in wide release in theaters Wednesday, centers on the conflict between two royal sisters in a fictional Nordic kingdom: exuberant young Anna (voiced by Kristen Bell) and her remote older sibling Elsa (Idina Menzel).

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Early reviews of the film have been positive, with critics noting that "Frozen" manages to avoid the common pitfalls of female-led animated movies that are either hopelessly old-fashioned fairy tales or leaden you-go-girl polemics.

Lee, one of the writers on Disney's 2012 video game movie "Wreck-It Ralph," joined Buck, the director of "Tarzan" and "Surf's Up," on the film in 2012, four years after the long-gestating project was greenlighted. "Especially because we have two female protagonists, it was great bringing Jen on," Buck said last spring as the two were still tinkering with their story.

Lee quickly had an impact on the sister story line, which hadn't been in previous iterations of the film, according to visual development artist Brittney Lee. "As soon as Jen came on, I suddenly saw my sister and I in the sisters," Brittney Lee said. "I recognized these two are real girls. Once a female perspective was present in the writing, it was so much easier to get behind it."

Jennifer Lee said she attempted to humanize Anna, who may be the first Disney princess to have gas, and to beef up, quite literally, the male characters. "I kept saying, 'Can we give Hans thighs, 'cause that's kind of appealing?' They were so little."