A source of deep concern for Eleonora was the War of the Mantuan Succession (1628–1631), which began after the deaths of her brothers Francesco IV (1612), Ferdinando (1626) and Vincenzo II (1627) without surviving legitimate male heirs. During the war between the Emperor, King Philip IV of Spain and Duke Charles Emmanuel I of Savoy on one side (who supported Ferrante II Gonzaga, Duke of Guastalla) and King Louis XIII of France and the Republic of Venice (who supported Charles Gonzaga, Duke of Nevers) in the other side, the Imperial army captured and sacked Mantua, the Empress' homeland.