Well, how well do you know the Theosophical and post-Theosophical authors in early 20th century occult circles in Europe and the US? HP Blavatsky was among those who talked about the rise of a Russian great culture in the near future and Katherine Tingley was one who talked about the emergence of an American great culture further out. (They didn't use that terminology -- the labels in those days were "root races" and "sub-races," because you could still use the r-word back then -- but the concept is the same; I translated it into Spenglerese to make it easier for people these days to understand it.)