Pedro Téllez-Girón, 3rd Duke of Osuna

Pedro Téllez-Girón, 3rd Duke of Osuna (17 December 1574 – 24 September 1624) was a Spanish nobleman and politician. He was the 2nd Marquis of Peñafiel, 7th Count of Ureña, Spanish Viceroy of Sicily (1611–1616), Viceroy of Naples (1616–1620), a Knight of the Order of the Golden Fleece since 1608, Grandee of Spain, member of the Spanish Supreme Council of War, and the subject of several poems by his friend, counselor and assistant, Francisco de Quevedo.

He served as a footsoldier and climbed the ranks, an unusual career for an aristocrat, during the Eighty Years' War. As Viceroy of Sicily and Naples, Osuna reorganized the local administration with new strategies and ships, and implemented a highly profitable and successful privateering system against the Ottoman Empire, the Republic of Venice and the Barbary corsairs. Despite counting solely on local resources, he maintained Spanish dominance in the Mediterranean during the ten years of his mandates, producing victories like Cape Corvo, Cape Gelidonya, Constantinople and Ragusa. At his peak, his individual naval power is believed to have rivaled that of the Sultan of the Ottoman Empire.

Although a favourite of King Philip III, he faced much obstruction from his court, which he ameliorated by buying political influence with booty from his campaigns. Osuna was eventually deposed in 1620, undoing most of his work, in midst of the unstability caused by the fall of the royal minister Francisco de Sandoval, Duke of Lerma. Venetians claimed Osuna had participated in a conspiracy to take over Venice, while the Neapolitan aristocracy purported he intended to secede from Spain and become King of Naples. He denied all accusations and died in prison while awaiting for judgement.