Conquest of Tunis (1535) participant Ottoman Empire
Background
In 1533, Suleiman the Magnificent ordered Hayreddin Barbarossa, whom he had summoned from Algiers, to build a large war fleet in the arsenal of Constantinople. Altogether 70 galleys were built during the winter of 1533–1534, manned by slave oarsmen, including 2,000 Jewish  ones. With this fleet, Barbarossa conducted aggressive raids along the coast of Italy, until he conquered Tunis on 16 August 1534, ousting the local ruler, theretofore subservient to the Spanish, Muley Hasan.  Barbarossa thus established a strong naval base in Tunis, which could be used for raids in the region, and on nearby Malta.Charles V assembled a large army of some 30,000 soldiers, 74 galleys (rowed by chained Protestants shipped in from Antwerp), and 300 sailing ships, including the carrack Santa Anna and the Portuguese galleon São João Baptista (the most powerful ship in the world at the time) to drive the Ottomans from the region. The expense involved for Charles V was considerable, and at 1,000,000 ducats was on par with the cost of Charles' campaign against Suleiman on the Danube. Unexpectedly, the funding of the conquest of Tunis came from the galleons sailing in from the New World, in the form of a 2 million gold ducats treasure extracted by Francisco Pizarro in exchange for his releasing of the Inca king Atahualpa (whom he nevertheless executed on 29 August 1533).Despite a request by Charles V, Francis I denied French support to the expedition, explaining that he was under a three-year truce with Barbarossa following the 1533 Ottoman embassy to France. Francis I was also under negotiations with Suleiman the Magnificent for a combined attack on Charles V, following the 1534 Ottoman embassy. Francis I only agreed to Pope Paul III's request that no fight between Christians occur during the time of the expedition.