The Barbary States, after the decline of the Arabian power, were enveloped in darkness, rendered more palpable by increasing light among the Christian nations. At the twilight of European civilization they appear to be little more than scattered bands of robbers and pirates, "land-rats and water-rats" of Shylock, leading the lives of Ishmaelites. Algiers is described by an early writer as "a den of sturdy thieves formed into a body, by which, after a tumultuary sort, they govern,"[28]--and by still another writer, contemporary with the monstrosity which he exposes, as the "theatre of all crueltie and sanctuarie of iniquitie, holding captive, in miserable servitude, one hundred and twentie thousand Christians, almost all subjects of the king of Spaine."[29] Their habit of enslaving prisoners captured in war and piracy arousing at last the sacred animosities of Christendom, Ferdinand the Catholic, after the conquest of Granada, and while the boundless discoveries of Columbus, giving to Castile and Leon a new world, still occupied his mind, found time to direct an expedition into Africa, under the military command of that great ecclesiastic, Cardinal Ximenes. It is recorded that this valiant soldier of the Church, on effecting the conquest of Oran, in 1509, had the inexpressible satisfaction of liberating three hundred Christian slaves.[30] [28] A Discourse concerning Tangier: Harleian Miscellany, Vol. V. p. 522. [29] Purchas's Pilgrims, Vol. II. p. 1565. [30] Prescott, History of Ferdinand and Isabella, Vol. III. p. 308. Purchas's Pilgrims, Vol. II. p. 813. To stay the progress of the Spanish arms the government of Algiers invoked assistance from abroad. Two brothers, Horuc and Hayradin, sons of a potter in the island of Lesbos, had become famous as corsairs. In an age when the sword of the adventurer often carved a higher fortune than could be earned by lawful exertion, they were dreaded for abilities, hardihood, and power. To them Algiers turned for aid. The corsairs left the sea to sway the land,--or rather, with amphibious robbery, took possession of Algiers and Tunis, while they continued to prey upon the sea. The name of Barbarossa, by which they are known to Christians, is terrible in modern history.[31] [31] Robertson, History of Charles the Fifth, Book V. Haedo, Historia de Argel, Epitome de los Reyes de Argel. MILITARY EXPEDITIONS AGAINST WHITE SLAVERY.