Expansion and Intensification of Communication and Exchange Networks Key Concept 3.1

Trade Improved transportation technologies and commercial practices led to an increased volume of trade, and expanded the geographical range of existing and newly active trade networks. Silk Roads, Sea Roads, Mediterranean Network, Sand Roads, Turquoise Roads all actively exchanged people, goods, disease and ideas among their connections. Abbasid Empire, Byzantine Empire, Mongols, Mali, Swahili Coast, Srivijaya, China and others all took advantages of their locations on the trade routes to establish powerful empires supported by their governments.

Trade Cities The expansion and intensification of trade networks in the post-classical period led to the rise of new cities as major trade hubs. Cities became the collection points where craft items were massed for bulk sale, the crossroads of major trade routes, and the ports connecting zones of trade together.

Examples of Trade Cities As a member of the Hanseatic League, the northern Russian city of Novgorod was vital in connecting European merchants with their Arab and Byzantine counterparts. Its surrounding marshes and thick forests protected it from the Mongol conquests allowing its importance for the coveted trade in fine furs to be uninterrupted.

Examples of Trade Cities In southeast Asia Malacca became an important city in the spice trade. It was a collection point for spices grown on tiny islands across Indonesia. In Malacca they were packaged and sold in bulk on the Indian Ocean. The city's location on the straits of Malacca allowed it to collect tolls and control passage.

Examples of Trade Cities The location of Timbuktu on the southern rim of the Sahara Desert raised its importance for trans- Saharan caravan trade. It became an exchange point for west African gold and north African salt. Because of the trade in books, the city also became an important city for Islamic scholarship and education.

Examples of Trade Cities Hangzhou was located near China's southern coast and on the Grand Canal which connected it across 1000 kilometers to Beijing. It was a departure point for Chinese goods to Korea, Japan, southeast Asia, and the Indian Ocean trade network. It became the capital of China during the Southern Song Dynasty.

Luxury Exchange and Change  During this period (600-1450 C.E.) interregional trade in luxury goods began to recover from its decline after the fall of Eurasian classical civilizations. Luxury goods have important symbolic meanings in societies. As markers of status, they testify to expenditures arising out of surpluses far beyond necessity.  Manufactured primarily for external markets, luxury goods bear an association with all things exotic and foreign. Most have rather mundane uses: silver plates and porcelain vases, silk clothing, and spices to enhance food. In these domestic settings luxury goods are "perceived as expressions of taste and civility."

Credit and Economic Exchange Trade in luxury goods was also facilitated by innovations in forms of credit and economic exchange. Between 600 and 1450, China devised a relatively safe method to make large payments across a vast distance. Special documents, called "flying money," allowed merchants to pay for goods or taxes without having to transport coins in bulk.  From Arabs, the practice spread to Western Europe where Italian merchants advanced this method into bills of exchange. Merchants used bills of exchange to purchase imported goods without the hazards of carrying an expensive medium of exchange. The bills, which worked like modern checks, required the existence of two established networks, one of bankers and another of merchants. 

Credit and Economic Exchange A merchant would place his wealth in the safe keeping of a banking house which would in turn issue a bill of credit that could be used to purchase goods imported from outside the local economy. The exporter of the goods would then present the bill for payment to his local representative of the banking network.  Of course, all of this had to take place within a framework of laws and courts to reduce the risks involved in such transactions. 

Building Projects – East Vs. West States could also take on massive engineering projects to increase trade. China – Grand Canal Western Eurasia never reestablished centralized rule and consequently did not have the benefit of such broad state projects.

Empires and Trade As in the classical age, empires facilitated trade and brought large areas and new people under their economic management. These are great examples of the impact of state building on networks of communication and exchange. 

China In the 7th century, China's Tang emperor sent several military expeditions to the northwest. The purpose of these was to defend the border against nomads, particularly the Turks, but also to take control of much of the western trade routes.  This expansion (which was eventually stopped by the Abbasids at the Battle of Talas in 751) brought many ethnic groups into China's cities. These groups in turn provided commercial links to nomadic and settled people of their Central Asia homelands. As a result, Chang'an (Xian) became intensely cosmopolitan. Serving as both the eastern terminus of the Silk Roads and the northern end of the Grand Canal, this city had large communities of non-Chinese ethnic groups who had settled there to take advantage of trade. By the 9th century, Uighurs dominated money lending, Sogdians ran the popular imported wine shops, and Turks were involved in the trade of many goods and Buddhist relics. 

Eurasia Byzantine: As with all empires, the expansion of the Byzantine empire broadened the groups of people participating in commerce. This began in the previous time period when Justinian temporarily conquered parts of northern Africa and Italy from the Vandals. Although these conquests were temporary, Byzantine trade connected Constantinople with commercial cities such as Alexandria and Tripoli as well as the islands of Crete and Sicily. When the Italian city-states emerged, they depended on imports of grain and textiles coming in from the Byzantine Empire. [31] The Empire also served as an important connection between Mediterranean trade and the Arab world. Another group of people pulled into the orbit of Byzantine trade was the state of Kievan Rus, or Russia. Kiev was an important mid point on the north/south trade routes connecting Constantinople to the fur traders of Novgorod and Scandinavia.

Asia - Mongols Having dissolved tribal loyalties and forged an unstoppable nomadic cavalry on the Central Asia steppes, Genghis Khan went on to conquer the largest land empire in history. The duration of the Mongol Empire was short compared to others, but never before or since has a single empire controlled the Eurasian land mass from China to Eastern Europe. When the conquests were done the entire length of the Silk Roads was in their domain and the Mongols settled down and enjoyed the benefits of trade. In an era known as the Pax Mongolica, or Peace of the Mongols, trade flourished under the protection of a flexible legal system and diplomatic protocols. They punished thieves and pirates. To extend commercial connections to Western European markets, the Mongols encouraged the building of port cities such as Kaffa on the Black Sea. They pushed trade outside of their empire by forcing Chinese to emigrate to South East Asia and form merchant communities in the trading ports there. In Cambodia, Vietnam, the Malay peninsula and Java, Chinese diaspora communities connected Mongol trade routes to foreign trading ports of the Indian Ocean network

spread of Islam The Islamic Caliphates. Unlike some other belief systems, Islam has been pro-trade from the beginning (Mohammed was a merchant) and trade accounted in part for the rapid spread of the faith. Merchants traveled farther than armies and took their religion to remote areas of Eurasia. As new areas were incorporated into the Dar al Islam, its protective legal system and positive acceptance of merchants created welcome haven of exchange. Banks and credit emerged. Crops such as rice, wheat, eggplant and citrus were transplanted across Islamic civilization thus creating year-round cultivation in some areas. The trans-Saharan trade in salt took Islam to West Africa thus bringing the Sub-Saharan region into Afro-Eurasian networks. Seeking furs from northern Europe, Muslim merchants traveled to Russia and Scandinavia with silk and metal wares. The nature of the Indian Ocean trade it perfect for carrying bulk items such as spices, and Islam diffused to the Africa's Swahili Coast. In South East Asia, the port city of Malacca became an Islamic Sultanate around the year 1400 and remained so until the Portuguese showed up 

Impact of the movement of people There was continued diffusion of crops and pathogens, including epidemic diseases like the bubonic plague, throughout the Eastern Hemisphere along the trade routes.  The movement of people had environmental effects. New tools and crops are carried on the backs of migrations and these can't help but alter man's relationship to the land.  Bantus in Africa changed landscape linguistically as well as environmentally as irrigation and terracing techniques created agricultural production that led to larger populations. Increase in the use of cattle expanded the population but also caused land erosion Animals taken by the migrating Polynesians had significant environmental consequences. In Hawaii the pigs they brought destroyed much of the indigenous flora and fauna. Much worse were the consequences of large edible rats the Polynesians carried to Easter Island. The pigs devoured the nuts and seeds from trees thus preventing them from replenishing. Probably to appease their gods, the Polynesians cut most all of the mature trees. Soon there was nothing left to make boats for fishing. After having eaten everything on the island they could, including their dogs, the population suffered a catastrophic collapse.