Two genres of southern music came out of the late 60s/early 70s; southern rock and country rock. The grandpappy of country rock has to be this guy..
"Faithful follower of Brother John Birch", heh. As for southern rock, the Allman Brothers paved the way but by far the most famous act was Lynyrd Skynyrd. While not a huge fan I did like a lot of their stuff, and even some of the offshoot material like this effort from surviving members Gary Rossington and Allen Collins:
.38 Special came along about the same time and had a very melodic sound that was perfect for rock radio, and also featured a Skynrd connection with Donnie Van Zant, the brother of the late Ronnie, in the band. Here's my favorite from them.
Kind of an aside, but back in the day the talented Todd Rundgren once commented to a reporter from a music magazine that southern rock players were "dumb and stupid". Can't find the quote now but in looking around I did learn that Rundgren helped to raise Liv Tyler and also has a son named "Rebop", and another son who plays shortstop in the Florida Marlins organization.