The Siege of Nice occurred in 1543 and was part of the Italian War of 1542–46 in which Francis I and Suleiman the Magnificent collaborated in a Franco-Ottoman alliance against the Holy Roman Emperor Charles V, and Henry VIII of England. At that time, Nice was under the control of Charles III, Duke of Savoy, an ally of Charles V. This is part of the 1543–1544 Mediterranean campaign of Barbarossa.