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.
Viking raids in the Rhineland
During this time, the Vikings attacked the Frankish Empire sailing their ships up the big rivers from the North Sea and Atlantic Ocean. Such raids mainly affected areas on the Seine and in modern-day Netherlands and Belgium. Previously, the Vikings had raided England (Lindisfarne, 793) and Ireland (Dublin, 795). In 820, the first major attack by Vikings on the Frankish Empire was recorded, taking place around the mouth of the river Seine, and at the same time other Vikings probably invaded Flanders. In 845, Paris was attacked for the first time with about 700 longships up the Seine. The Parisians bought the raiders off with 7,000 pounds of silver. By 926, thirteen of these payments have been documented in the Frankish Empire. The Elbe estuary and the already fortified city of Hamburg were attacked by Danish warriors in 845.