Τhe city is built upon the exact spot of the ancient city of Aigio. According to the findings of the excavations, the area was first inhabited during the Paleolithic era and it has been under continuous habitation since 2000 B.C. During the invasion of Dorians (1100 B.C.) in the greek peninsula, Achaeans from several areas (especially Argolida) migrated to the area and founded important cities such as Aigio and Patras. Aigio itself has been the religious and political headquarters of the Achaeans, as well as the capital of the Achaean Sympoliteia (an archaic community between cities) around 276 B.C. After an extensive period of occupation  from several cultures (Franks for approximately 200 years and Ottomans for another 400) and the peaceful migration of Albanian and Slavic population seeking for a better future, Aigio has been the first greek city to liberate from the Ottoman occupation (26th of March 1821) during the Greek Revolution.