MANTUA, the duchy of, a country of Italy, lying along the river Po, which divides it into two parts. It is bounded on the north by the Veronese; on the south, by the duchies of Reggio, Modena, and Mirandola; on the east, by the Ferrarese; and on the west, by the Cremonese. It is about 50 miles in length, and 25 in breadth; is fruitful in corn, pastures, flax, fruits, and excellent wine. Charles IV. the last duke of Mantua, being a vassal of the empire, took part with the French, in the dispute relating to the succession of Spain; for which reason he was put under the ban of the empire, and died at Venice in 1708. He having no heirs, the emperor kept the Mantuan in his own hands, and the duke of Savoy had Montferrat, which were confirmed to them by subsequent treaties. After the death of the emperor, in 1740, his eldest daughter, now empress-queen, kept possession of the Mantuan; and the governor of the Milanese had the administration of affairs. The Mantuan comprehends the duchies of Mantua, Guastalla, and Sabioneta; the principalities of Castiglione, Solforino, and Bosolo; likewise the county of Novellara. The principal rivers are the Po, the Oglio, and the Mincius; and the principal town is Mantua.