Historically, the period from 1500 BC–1 AD saw the Western Asian, Mediterranean, Chinese and Indian societies develop major networks for trade, such as the silk road. Europe's early trading routes included the amber road, which served as a network for long distance trade. Maritime trade along the spice route became prominent during the Middle Ages; nations tried to control this influential route. During the Middle Ages organizations such as the Hanseatic League, aimed at protecting interests of the merchants and trade, also became increasingly important.
In modern times, commercial activity shifted from the major trade routes of the Old World to newer routes between modern nation states. This activity was sometimes carried out without traditional protection of trade and under international free trade agreements, which allowed commercial goods to cross borders with relaxed restrictions. Innovative transportation of the modern times includes pipeline transport, and the relatively well known trade using rail routes, automobiles and cargo airlines.
- Denemark 2000: 274
- Burns 2003: 213
- Donkin 2003: 169
- Dollinger 1999: 62
- free trade. The Columbia Encyclopedia, Sixth Edition. 2001-05.
- Burns, Thomas Samuel (2003). Rome and the Barbarians, 100 B.C.-A.D. 400. Johns Hopkins University Press. ISBN 0801873061.
- Denemark, Robert Allen; et al. (2000). World System History: The Social Science of Long-Term Change. Routledge. ISBN 0415232767. Explicit use of et al. in:
- Dollinger, Philippe (1999). The German Hansa. Routledge. ISBN 041519072X.
- Donkin, Robin A. (2003). Between East and West: The Moluccas and the Traffic in Spices Up to the Arrival of Europeans. Diane Publishing Company. ISBN 0871692481.