While the “Nine Old Men” are well-documented and justly praised as the legendary animators of the Disney classics overseen by Walt — “Snow White and the Seven Dwarfs” (1937) through “The Jungle Book” (1967) — it’s gone unnoticed how the directors made their mark on these movies. That changes with the release of “Directing at Disney: The Original Directors of Walt’s Animated Films” by Disney historian Don Peri and Pete Docter , Pixar’s chief creative officer and Oscar-winning director of “Soul,” “Inside Out,” and “Up.” Peri and Docter, who spent more than a decade on the book, reveal for the first time the organizational structure for directing at Disney and how the role of the director progressed.

Peri, who had a fundamental understanding of how films were made at Disney, spent years at the Walt Disney Animation Research Library, combining interviews, documentation, and a diary into a methodology of the directors’ roles and how they collaborated with the animators. On the early features, the directors were known as supervising directors, overseeing the work of sequence directors, who previsualized and planned their sections with the animators and worked with the voice actors until the mid-’60s. But Disney oversaw every facet of production, focusing on story, and had final approval of everything.

Then a supervising producer role was introduced in the ’40s and the directors took on greater responsibility in implementing Disney’s cre.