 The territory of the province was first colonized by the Greeks, who founded the colony of Adria in the 12th-11th centuries BC.During the 6th and 5th centuries BC Etruscans and Venetians inhabited the area, followed by the Romans.In the Middle Ages the region was ruled by the Este as part of the Duchy of Ferrara, but Rovigo was not an administrative unit of the duchy, and there was more than one "Podesteria" for each side of the Po river.