The Allman Brothers song is indeed based on Hank Williams, though it's not exactly a cover. House of the Rising Sun isn't an original either (it's an old folk song), although the Animals did make it famous in popular culture.
I am so sad that only 15% knew Arlo Guthrie. He was the 18 y/o son of Woody Guthrie who was arrested for littering, the evidence was photos that were placed before a blind judge, he was found guilty, and that littering conviction keep him out of Vietnam. Then he wrote an 18-minute song about it that became a hit and it was turned into a movie in which the original arresting officer and judge played themselves. You can't make this stuff up. And he's still performing. Check him out.