In 1484, after the end of the War of Ferrara, the Republic of Venice took possession of the area north of the Tartaro-Canalbianco, named "Polesine of Rovigo" by the Este because of its characteristic of being an island between rivers; other lands outside the proper named "Polesine of Rovigo" were also annexed, including the areas of Adria, Polesella and Guarda Veneta. All these areas established the Territory of Polesine inside the "Domini di Terraferma" (Mainland State) of the Republic of Venice.