In an eagerly anticipated new story, “Harry Potter” author J.K. Rowling has transported her world of magical wizarding across the Atlantic – and some Native American commentators are not happy with the result, saying it exploits and distorts Native culture.

Rowling posted the first part of the four-part series “The History of Magic in North America” to her Pottermore website Tuesday. The mock-academic collection, published over four days, promises to “enlighten readers about a previously unexplored corner of the wizarding world, taking us into the lives of North American witches and wizards, their history and their magic, and introduces audiences to a new era of the world that J.K. Rowling has created,” according to Pottermore’s publicity rollout.

But the magical world depicted in the first story, “Fourteenth Century–Seventeenth Century,” isn’t purely drawn from Rowling’s imagination. One passage references the Navajo legend of the “skin walker”:

“The legend of the Native American ‘skin walker’ – an evil witch or wizard that can transform into an animal at will – has its basis in fact. A legend grew up around the Native American Animagi that they had sacrificed close family members to gain their powers of transformation. In fact, the majority of Animagi assumed animal forms to escape persecution or to hunt for the tribe.”

Adrienne Keene, a Cherokee writer who created the Native Appropriations online forum, wrote in a blog post Tuesday that Rowling’s take recklessly misrepresents a tradition that still has very real meaning to many.

The belief in skin walkers “has a deep and powerful place in Navajo understandings of the world,” Keene wrote. “It is connected to many other concepts and many other ceremonial understandings and lifeways. It is not just a scary story.”