He was appointed a cardinal at the age of 20. A few years after his elder brother, Duke Francesco IV, died in 1612 without male heirs, he renounced the ecclesiastical career and succeeded his brother in both the Duchy of Mantua and the Duchy of Montferrat.
In 1616 he secretly married Camilla Faà di Bruno, whom he divorced in the same year. Their son Francesco Giacinto Teodoro Giovanni Gonzaga, although accepted at court, was not made Ferdinando's heir. He died of the plague at the age of 14, during the 1630 siege of Mantua.[2] On 16 February 1617 Ferdinando married Caterina de' Medici (1593–1629), the daughter of Ferdinand I, Grand Duke of Tuscany.[1]
Ferdinand Gonzaga died in 1626. His younger brother Vincenzo II inherited the duchy.[1]
Grendler, Paul F. (2009). The University of Mantua, the Gonzaga, and the Jesuits, 1584–1630. Johns Hopkins University Press.
Parrott, David (1997). "The Mantuan Succession, 1627–31: A Sovereignty Dispute in Early Modern Europe". The English Historical Review. CXII, Issue 445, February (445). Oxford Academic: 20–65. doi:10.1093/ehr/CXII.445.20.
