Interracial marriage
From AD 839, Viking Varangian mercenaries who were in the service of the Byzantine Empire, notably Harald Sigurdsson, campaigned in North Africa, Jerusalem and other places in the Middle East during the Byzantine-Arab Wars. They interbred with the local population as spoils of warfare or through eventual settling with many Scandinavian Viking men taking Arab or Anatolian women as wives. There is archaeological evidence the Vikings had established contact with the city of Baghdad, at the time the center of the Islamic Empire, and connected with the populace there. Regularly plying the Volga with their trade goods (furs, tusks, seal fat, seal boats and notably female slaves; the one period in the history of the slave-trade when females were priced higher than males), the Vikings were active in the Arab slave trade at the time. These slaves, most often Europeans that were captured from the coasts of Europe or during war periods, and sold to Arabic traders in Al-Andalus and the Emirate of Sicily.
History of the Netherlands
In the 9th and 10th centuries, the Vikings raided the largely defenceless Frisian and Frankish towns lying on the coast and along the rivers of the Low Countries. Although Vikings never settled in large numbers in those areas, they did set up long-term bases and were even acknowledged as lords in a few cases. In Dutch and Frisian historical tradition, the trading centre of Dorestad declined after Viking raids from 834 to 863; however, since no convincing Viking archaeological evidence has been found at the site (as of 2007), doubts about this have grown in recent years.