A great deal of the written record of indigenous religion in North America was made between the 1880s and the 1930s by ethnographers working on an explicit assumption: that the peoples they were recording were about to disappear, and that the urgent task was to collect everything before they did. The assumption was wrong. The nations are here.
The work produced under it is genuinely valuable and genuinely compromised. Ceremonies were transcribed, songs recorded on wax cylinders, and objects removed to museums, often from people under enormous pressure and sometimes without any meaningful consent. Knowledge that was restricted within a community, held by particular societies or particular sexes or released only at particular times, was published in volumes anyone could buy.
The pressure was not incidental to the recording. The same decades saw the Sun Dance and the potlatch prohibited by law in the United States and Canada, and children removed to boarding and residential schools where their languages and practices were punished. Ceremonies were being documented by scholars and suppressed by governments at the same time.
Later law changed the terms. The Native American Graves Protection and Repatriation Act of 1990 established a process for returning human remains and certain sacred objects, and museums now negotiate access with the nations concerned.
The atlas treats restricted knowledge as restricted, and names a closed practice as closed rather than describing it from a hundred-year-old monograph.