Wikipedia
Holmgang (hólmganga in Old Norse and modern Icelandic, holmgång in Swedish, holmgang in Danish and Norwegian bokmål and nynorsk) is a duel practiced by early medieval Scandinavians. It was a recognized way to settle disputes.
Holmgang can be translated as "to go to (or walk on) a small island" or simply "holme going", perhaps a reference to the duels taking place upon a small piece of hide or cloak placed on the ground. The name may also derive from the combatants dueling on a small island or holme, as they do in the saga of Egill Skallagrimsson.
At least in theory, anyone offended could challenge the other party to holmgang regardless of their differences in social status. This could be a matter of honor, ownership or property, demand of restitution or debt, legal disagreement or intention to help a wife or relative or avenge a friend.
Holmgangs were fought 3–7 days after the challenge. If the person challenged did not turn up for the holmgang, the other man was considered just in his challenge. If the offended party does not turn up for the holmgang, they were deemed niðingr, and could have been sentenced to outlawry. In effect, if they were unwilling or unable to defend their claim, they had no honor. Sometimes a capable warrior could volunteer to fight in the place of a clearly outclassed friend.
Usage examples of "holmgang".
Some of it, I confess, was spilled in no public cause, but for the protection of mine own honour in the private duello or holmgang, as it was called among the nations of the north.
Let the holmgang begin, and he who is challenged may strike the first blow!
This was no holmgang, with rules and a fixed order of blows and first blood meaning victory.
Shef, sparing just one glance from his nearest enemy, recognized all three: Halvdan Ragnarsson, who had umpired his holmgang at York, Ubbi Ragnarsson the grizzled, and between them Sigurth, who had taken Shef's eye at Bedricsward.