After the War of Ferrara in 1484 the Republic of Venice started ruling over the northern part of Polesine; the Venetians designated it a "territorio" whose capital was Rovigo, thus giving the area an administrative unity for the first time. This can be viewed as the start of the province of Rovigo, though its extent was a less than today; the borders were set as the Canal Bianco river with few exceptions: the territories of Polesella, Guarda Veneta, Adria and the delta of the Po were included in the Venetian "territorio" of Rovigo.