I'm a little curious as to why you think that Africans were a significant force in fighting Indians? I don't know very much about the time period, so I'm just wondering what led you to this question?

I don't know the number counts but there are very few historical instances of African-Americans fighting Native Americans in combat. Additionally the European-American population in the US far outstrips the African-American population, so definitely more European-Americans have killed Native Americans throughout history.