Going back to the message that started this thread, Ron was on the right track in explaining why these names aren't household in most/many circles. Other African American folk singers were widely recognized during the 60s -- to the ones named or who should have been named above (Josh White, Odetta, Miriam Makeba, Leadbelly) -- add, for example Gus Cannon and his Jug Stompers, from a much earlier era but warmly embraced when they played NYC for the Friends of Old Time Music back in '63 or thereabouts. Most of the recognized African American musicians in the 60s were older and had started playing before the 60s. The younger folk musicians who began playing in the 60s were overwhelmingly white.

And as to encountering racism in America, either in the 60's or today -- now THERE'S a surprise! The only news would be if someone didn't encounter racism when interacting with America.