Barbarossa [Ital.,=red-beard], surname of the Turkish corsair Khayr ad-Din (c.1483-1546). Barbarossa and his brother Aruj, having seized (1518) Algiers from the Spanish, placed Algeria under Turkish suzerainty. He extended his conquests to the rest of the Barbary States. Between 1533 and 1544, as admiral of the Turkish fleet under Sulayman I, he twice defeated Andrea Doria and ravaged the coasts of Greece, Spain, and Italy. His able son Hasan (d. 1572) succeeded him in Algeria.