The Holmgang was the usual solution to disputes in the Germanic cultural sphere during the Norse Iron Age, the Vandal Age, and the Viking Age (800-1050 AD) and beyond.
There were detailed rules for the Holmgang. If the duel took place near the coast, one chose a small (uninhabited) island or a skerry (see also: Holm). In the inland, one sought out a secluded spot. With Christianization, Holmgang was banned, first in Iceland, later in Norway.
"So the Holmgang law was: the fighting rug should be five cubits long, with loops at the four tips. Stakes with a head end were to be driven into these, which were called 'Tjösnur'. The one who did this should go to the stakes that he saw the sky between his feet, grabbed his earlobe and muttered the spell that was later recited at the so-called 'Tjösnur sacrifice'. Three fours were to be drawn around the carpet, each a foot wide. Four poles were to be placed at the edges of these fours. They were called the 'hazels'. When this was done, the battlefield was 'hazed in'. Each man was given three shields. If they were hazed, then he was to step back onto the battlefield carpet if he had left it before, and now defend himself with the weapons alone. The challenged fought first. If one was wounded, so that blood flowed on the carpet, then one was not allowed to fight further. If one set foot outside the hazels, then it was said, 'He is giving way,' he stepped beyond them with both: 'He has fled.' In front of each of the fighters, his partner was to hold the shield. The one who was most wounded, to redeem his life, had to pay three marks of silver."
- Kormák's saga ch. 10