SARACENS, CRUSADERS, AND SELJUK TURKS 13 the capture of Constantinople by the Crusaders, with the Earl of Flanders raised to the Imperial dignity, promised to mediaeval Italy a restoration of the affluence which had flowed from the East to ancient Rome. But new forces were upheaving in further Asia, destined to overthrow Saracen culture and Christian trade with a common ruin. About 1038 A. D. the Seljuk Turks had burst upon Persia. Two centuries later the gathered strength of the Mongols poured over Asia under Chingiz Khan (1206), ravaged through Poland under his son, and under his grandson wrested back Russia to barbarism. In 1258 Baghdad went down before the Mongol hordes, and the Saracenic caliphate was shattered.. The tidal wave of devastation spread over the countries of the Syrian caravan track, at times leaping forward in irresistible masses, then pausing to gather volume for the next onrush. In 1403 Timur drove the Knights Hospitallers forth from Smyrna to their island stronghold at Rhodes. By that time the Mongols and Turks had partially blocked the middle trade-route from the Persian Gulf to the Mediterranean, and were preparing to seize the northern trade-route by way of the Black Sea. The main northern route started from the Indus valley and crossed the western offshoots of the Him- alayas and the Afghan ranges to the Oxus. On that great river of Central Asia the products of India were joined by the silks of China, conveyed from the western province of the Celestial Empire by a caravan journey of eighty to a hundred days. The united volume of
