Holmganga, known as duels or single combats were prevalant in viking society until they were banned as a way of settling disputes in 1015 by King Erik. There were many causes of disputes that would lead to a combat, insults, the killing of a family member, infidelity or fighting over a woman or whatever. The list is endless. But when something like this happened it was usually determined by single combat that was often fought to the death.

Sometimes a lesser or weaker opponent could see that he had no chance of victory in such a fight so he submitted and surrendered his wealth and goods, sometimes even his wife to appease the opponent. This was an acceptable alternative as vikings were not generally dishonest in their dealings.

Single combats generally took place in a designated area of about a few square metres spread out on a cloak. If a man then stepped outside of this area during the fight, they were labled a "nithing", a coward. Each viking had 3 shields with which to defend himself with. If one of them got hurt, and their blood touched or smeared the cloak, they were allowed to stop the fight, and the one with the least number of wounds would be declared the winner.

Quite frequently fighting was until death. The loser, if he was still alive, had to pay his adversary in silver. If he died, all his equipment went to the winner. And it is because of this many berserkers would purposely fight Holmganga's, and this is most likely one of the reasons why they traveled around fighting for payments.



sources:
http://hjem.get2net.dk/fyrkat/english/Krigere.html
http://www.florilegium.org/?http%3A//www.florilegium.org/files/NORSE/Berserkergang-art.html