Cosimo I, Duke (1537-1569), Grand Duke (1569-1574) (Duchy of Florence) : All Data

Cosimo I was the Duke and later Grand Duke of the Duchy of Florence from 1537 to 1574. During his reign, he faced several significant conflicts. One of the most important wars was the War of Siena, which took place from 1551 to 1559. This war saw Cosimo I leading Florence against the Republic of Siena, ultimately resulting in the annexation of Siena into the Grand Duchy of Tuscany. Another notable conflict was the Ottoman-Portuguese War, which occurred from 1538 to 1559. Although Cosimo I was not directly involved in this war, it had a significant impact on the Mediterranean region and influenced his foreign policy decisions.