Several theories have been woven and advanced to explain the origin of the now famous municipality of Dinas, which had been the cradle of Islamic culture and civilization and the bulwark of anti-Hispanic colonization in the entire Baganian Peninsula of Zamboanga del Sur. According to ancient history which has been accepted and advocated by the scions of the great grand Sultan Kudarat, a descendant of the renowned Shariff Kabungsuan of Maguindanao was that the name Dinas was taken from a Maguindanao term Di Nas where “Di” means “Not” and “Nas” means “Bad Luck or Unlucky”. Hence, the early settlers who migrated from the province of Cotabato found their new haven as not unlucky or “Di Nas” because the mouths of all rivers emptying into the coastlines are facing East which according to their ancient belief is a sign of good luck. Today nearly the half of the population are Maguindanaon Muslims.
Dinas is politically subdivided into 30 barangays.