Remember, medieval Iceland was an early attempt at anarcho-capitalist utopia. When Harald Fairhair declared himself King of Norway, the Norwegians who refused to bend the knee fled west to build a makeshift seastead on a frozen volcanic island. No lords, no kings, no masters. Only lawsuits. So, so many lawsuits.
Once a year, the Icelanders would meet at the Althing, a free-for-all open-air law court. There they would engage in that most Viking of pastimes - suing each other, ad nauseam, for every minor slight of the past six months. Offended parties would sell their rights to prosecute a case to the highest bidder, who would go around seeking fair arbitrators (or, in larger cases, defer to a panel chosen by chieftain-nobles called godi2). Courts would propose a penalty for the losing side - usually money. There were no police, but if the losers refused to pay, the courts could declare them “outlaws” - in which case it was legal to kill them. If you wanted to be a Viking in medieval Iceland, you needed a good lawyer. And Njal was the greatest lawyer of all.