Although I can't find any information on what the budget for White Buffalo was, I suspect that the Dino de Laurentiis Corporation provided a reasonable amount of money considering they were 1977 dollars. I mention this because the most typical comments state that the laughable buff effects were due to low budget constraints.
But consider this. 2001: A Space Odyssey's effects were set to screen nine years before 1977 and Star Wars was released the same year as White Buffalo.
So special effects, although not CGI, were certainly advanced enough to satisfy those who have commented negatively here. So ... why were more advanced effects not used?
My theory is that the makers wanted to create a surreal, dreamlike feeling, much like it might have been to listen to an Indian storyteller around a village campfire a hundred and fifty years ago. In those times, human imagination could not have constructed the special effects images that we take for granted in our present-day monsters. Modern effects would detract from the misty, myth-like ambiance of this movie ... the myth of James Butler Hickok, the myth of Crazy Horse, the myth of the white buffalo.
When combined with John Barry's haunting score, this movie really has an effect on me. I give it an 8 out of 10 and hope to see it on a 1.85:1 widescreen DVD soon. I also hope the sound will be remastered better than the bloody mono track many of these cheap disk production companies are passing off on us!