Willa Cather biographers are in agreement that her character
Blind D'Arnaut was based on Blind Tom.  In her book O'Connell also
quotes from Cather's review of Blind Tom's performances.

O'Connell's book also covers in great detail the connection
between Blind Tom and Twain's relative by marriage Henry Watterson.
Watterson's comments as well as others are available online from
this article:

http://www.twainquotes.com/archangels.html

The author of _Ballad of Blind Tom_ is Deirdre O'Connell of
Australia who currently works in news at SBS Australia. She spent
time in the U. S. researching Blind Tom and her insights into
American slavery are on target.

Barb