Contact. There certainly was contact by medieval traders with peoples of different lands. By the late ninth century the Vikings met Inuits in Greenland and North America, Celts in Ireland, and Angles and Saxons in Mercia, Northumbria, and East Anglia. Traders from the cities of Genoa and Pisa had met the Muslims in violent clashes at sea by the year 1000. The German princes' victory over the Danes at Bornhoven (1227) opened the way for south-coast Baltic merchants to dominate trade in Scandinavia. In the late thirteenth century the Venetians Marco Polo, his father, Niccolo, and his uncle Maffeo reached Mongolian China and became personally acquainted with one of the emperors, Kublai Khan.

Muslims. The Muslims, believers of the prophet Muhammed's religion, carried on trade in Europe as well as in Africa, China, and Central Russia, especially from 750 until 1055, under...