Complex sentence: Originally, it was only used by some of the Indigenous peoples of the Americas, notably the Plains Indians, but with the rise of pan-Indianism, numerous nations that did not originally have the sweat lodge ceremony have adopted it.
Split into simpler sentences: Originally, it was only used by some of the Indigenous peoples of the Americas, notably the Plains Indians. But with the rise of pan-Indianism, numerous nations that did not originally have the sweat lodge ceremony have adopted it.