Culture of Mithila Region Wikipedia
The Mithila region broadly comprises the Maithili speaking regions of Mithila, India and Mithila, Nepal. , 
Maithili is the mother-tongue of Maithils. The relationship of the Maithili community with the Bhojpuri and Magahi communities (their immediate neighbors) has been neutral. The age old cultural identity of Mithila is the paag. In recent years the Save the Paag Campaign slogan has been popular. While almost all Maithils have accepted Hindi(Urdu) or Nepali as a language for formal occasions, the retention of Maithili for cultural, social, familial, and literary purposes is common.