Formalized, regular, long-distance trade routes appear in the earliest human records at the beginning of the Bronze Age. Long-distance trade allowed an empire to supplement meager natural resources or import luxury goods. In the period of its existence, from 130 BCE to 1353 CE, the Silk Road helped connect eastern, central, and western Asia into a vast trade network, with goods flowing in multiple directions and with starting and stopping points all along the routes. The Byzantines traded in silk cloth, fine ivories, and delicate products of the goldsmiths’ and silversmiths’ art, slaves, and naval stores. Trade in the West included some high-value luxury goods but mainly ordinary items, such as plain pottery, raw wool, wool cloth, millstones, weapons, and slaves. The Kingdom of Ghana controlled trade in salt and gold by taxing both commodities as they moved from one side of Africa to the other. Some generalizations about the cultures outside of the Islamic-influenced kingdoms can be made.