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 Denmark
With the beginning of the Viking Age in the 9th century, the prehistoric period in Denmark ends. The Danish people were among those known as Vikings, during the 8th–11th centuries. Viking explorers first discovered and settled in Iceland in the 9th century, on their way from the Faroe Islands. From there, Greenland and Vinland (probably Newfoundland) were also settled. Utilizing their great skills in shipbuilding and navigation they raided and conquered parts of France and the British Isles.
They also excelled in trading along the coasts and rivers of Europe, running trade routes from Greenland in the north to Constantinople in the south via Russian and Ukrainian rivers, most notably along the River Dnieper and via Kiev, then being the capital of Kiev Rus. The Danish Vikings were most active in Britain, Ireland, France, Spain, Portugal and Italy where they raided, conquered and settled (their earliest settlements included sites in the Danelaw, Ireland and Normandy). The Danelaw encompassed the Northeastern half of what now constitutes England, where Danes settled and Danish law and rule prevailed. Prior to this time, England consisted of approximately seven independent Anglo-Saxon kingdoms. The Danes conquered (terminated) all of these except for the kingdom of Wessex. Alfred the Great, king of Wessex, emerged from these trials as the sole remaining English king, and thereby as the first English Monarch.