Ferdinand I (born July 30, 1549—died Feb. 7, 1609) was the third grand duke (granduca) of Tuscany (1587–1609), who greatly increased the strength and prosperity of the country.
The younger son of Cosimo I, Ferdinand had been made a cardinal at age 14 and was living in Rome when his brother Francis (Francesco) died without a male heir, and he inherited the grand ducal title (1587). He did not renounce his cardinalate until 1589, when he married Christine of Lorraine, daughter of Charles III of Lorraine, and a granddaughter of Catherine de Médicis through her mother, Claude de France. This marriage, moreover, symbolized his policy of rapprochement with France in order to counteract Spanish influence in Italy, where Tuscany’s independence and prosperity was assured by his skill at playing one great power off against another. For all his ecclesiastical background, he was a far more capable exponent of Cosimo’s policy than Francis had been.
Secret loans from Ferdinand helped Henry of Navarre, even before his conversion to Roman Catholicism, in his war to make himself king of France as Henry IV; and the occupation of the Château d’If by Tuscan forces (1591) obstructed Spanish designs on Marseille during the same war. There was some dispute between Ferdinand and Henry before Ferdinand withdrew his garrison from the Château d’If (1598), but their friendship was sealed by Henry’s marriage, in 1600, to Ferdinand’s niece Maria (Marie de Médicis). To preserve good relations with the Austrian Habsburgs, on the other hand, Ferdinand’s son Cosimo was married in 1608 to the archduchess Maria Magdalena, a first cousin of the emperor Rudolf II; and Tuscan forces helped the Austrians in their war against the Turks. The Knights of St. Stephen won notable victories over the Turks in the Ionian and Aegean seas (1605–09) and on the African coast (Bône, 1607).
Ferdinand’s wise administration, an increase of commercial activity, and the continuance of his predecessors’ plans for draining the marshes and for developing Livorno and its port (where political exiles from abroad were encouraged to settle) raised the grand duchy to a new zenith of prosperity. In Rome, as a cardinal before becoming grand duke, Ferdinand had distinguished himself as a lover of the arts and as the builder of Villa Medici; and in Tuscany under his rule Giovanni da Bologna and Buontalenti remained active among artists and architects. Ferdinand also patronized Giulio Caccini, Jacopo Corsi, and other musicians of the Camerata de’ Bardi, whose work marked the birth of opera in Florence.