Introduction : studying a system in formation -- The European subsystem: The cities of the Champagne fairs; Bruges and Ghent : commercial and industrial cities of Flanders; The merchant mariners of Genoa and Venice -- The mideast heartland: The Mongols and the northeast passage; Sinbad's way : Baghdad and the Persian Gulf; Cairo's monopoly under the slave sultinate -- Asia: The Indian subcontinent : on the way to everywhere; The strait and narrow; All the silks of China -- Conclusion : restructuring the thirteenth-century world system.