Hi, Yo - I found the "Brother John" lyrics on a terrific Smithsonian Folkways CD called "Crossroads: Southern Routes." It's an enhanced CD and it displays the lyrics as the song plays - but it moves too fast for me to be able to transcribe them.

MardiGras (Fat Tuesday, the day before Ash Wednesday), is known as Carnival or Karneval in much of Europe. I found an interesting article about the Mardi Gras Indians (click).
-Joe Offer-