Whilst Scandinavia was still in the Stone and Bronze stages of the development of civilisation, merchants came to the Baltic for furs, tin, and the yellow amber so highly prized as an ornament by the oriental women. Indeed Oppert has shown that ten centuries before the Christian era the Assyrians had at least indirect communication with the Baltic shores, the only locality known to the ancient world where the yellow amber could be procured. The references to amber in Homer and Hesiod have not passed without dispute, but the discoveries of Greek coins in various parts leave little or no doubt as to the existence of commercial routes, which went from the Black Sea, by the Dnieper, the Bug and the Dniester, to gain the basin of the Niemen and of the Vistula, and thence spread to the Baltic. The amber commerce in the hands of the Milesians and the Greeks found various routes. The Roman women were as passionately partial to amber ornaments as their sisters of the East, and there is sufficient testimony as to the commercial intercourse of Rome with the barbarians of the North. The Arabs, although in the Middle Ages they had the monopoly of the trade, were not its originators, but merely continued an intercourse that had existed from remote antiquity. The mediæval geographers had very little precise knowledge; but in the Mappa Mundi of the tenth century, in the British Museum, the parts of northern Europe indicated with the fewest misconceptions are the countries of the amber trade. The rapid conquest of western Asia by the Arabs was followed by those internal dissensions which led to the formation of independent kingdoms. The Samanides, who reigned in Persia and dominated the shores of the Caspian Sea, were the principal cultivators of the North trade. The Arabs, if they had little taste for maritime commerce, were admirably adapted to be the leaders of great caravans, by which the riches of the East were spread into far lands. From Egypt they went across the Sahara to Nigritia, from whence they brought gold, ivory, and slaves. Passing through Persia and Cashmere they worked in the direction of India. Crossing the immense steppes of Tartary, they entered China by the province of Shen-si. Their caravans to Europe passed by Armenia on the south, and by Bokhara and Khorassan on the east. There were great fairs at Samarcand, Teheran, Bagdad, and other places. The merchants directed their course to the Caspian, and halted at Derbend before ascending the Volga. The itinerary of these pilgrims of commerce can be reconstructed from the Kufic coins and accompanying ornaments that have been found at Kazan, Perm, Tula, Moscow, Smolensk, Novgorod, St. Petersburg, and other localities. The finds of Arabic moneys in the Russian Empire have occurred almost exclusively in the country watered by the Volga, which was the line of communication for the Arabs with the Slavs and Scandinavians of the Middle Ages. The shores of Germany, Lithuania, and Sweden were visited.