On 2 July 1621, Emperor Ferdinand II elevated the County of Guastalla to the rank of a duchy. Ferrante II Gonzaga became the first duke of the city, hoping to succeed in the future to the great Duchy of Mantua. Ferrante II died of plague in 1630 and was succeeded by his son, Cesare II. With him, Guastalla expanded its territory with the annexation of the lands of Dosolo, Luzzara and Reggiolo, until then owned by Mantua. In 1632, his son Ferrante III ascended to the throne. Having no male heir, he bequeathed the Duchy of Guastalla to his daughter's husband Ferdinand Charles, Duke of Mantua.
