The Holy League (, ) of 1571 was arranged by Pope St. Pius V and included almost all the major Catholic maritime states in the Mediterranean. It was intended to break the Ottoman Turks' control of the eastern Mediterranean Sea and was formally concluded on 25 May 1571. Its members were the Papal States, the Habsburg states of Spain, Naples and Sicily, the Republic of Venice, the Republic of Genoa, the Grand Duchy of Tuscany, the Duchies of Savoy, Parma and Urbino and the Knights of Malta. These states were to have a force of 200 galleys, 100 other ships, 50,000 infantry, 4,500 cavalry and adequate artillery ready by 1 April each year. Don Juan de Austria, illegitimate half-brother of King Philip II of Spain, was designated supreme commander. The League kept membership open for the Holy Roman Empire, France and Portugal, but none of them joined. The Empire preferred to maintain its truce with Istanbul, while France had an active anti-Spanish alliance with the Ottomans. Portugal was heavily engaged in its own Moroccan campaign and its ongoing maritime confrontations with the Ottomans in the Red Sea and the Indian Ocean and had no forces to spare.