Not really . Northern french are mixed between Picards, Normans, and somes Germans tribes. Southern French are more like basque, occitans... with a high amount of italians . Almost 50% of southern french have one italian in their family tree . Central french are mixed between Southern and Northern French. We just have the french language in common . But the regional languages in northern france are germanics, and in southern france are romane-occitan. But southern french who don't like northerner and northerner french who don't like southerner, I don't think it's a language problem, it's just a dumb racist problem