 Born in Ferrara, he was the first son of Cesare d'Este, Duke of Modena and Virginia de' Medici.In 1613 he took part in the war against Lucca and had a primary role in the assassination of count Ercole Pepoli, who was disputing the duchy with Cesare, at Ferrara (1617).In 1608 he was married to Isabella of Savoy, daughter of Charles Emmanuel I of Savoy.