Dambe fighting is the oldest fighting tradition I've seen and know of that is still around today.You can't get much older than African traditions.
Ironically the brutality of the MMA has made many of the traditional fighting arts more popular. It took away the image that "fighting is barbaric." I thank BJJ for that. and the UFC for push through when it was getting labeled as being barbaric. People now see the money in it so there's less resistance.