Oh short one,
Back has nothing to do with the front. My best guess... Something was spilled or dropped on rug....the fringe shows signs of something coffee,tea,whatever.
Then someone tried to clean it...looks like some dye bleed or just really bad pile distortion, rug pile got wet and was never groomed properly. Then some genius tried bleach or an oxymoron on it. Thats my best Sherlock Holmes or I could be completely wrong!