At some point in our military life, most of us pick up a nickname. Most of the time, the nicknames are hilarious...to everyone else. How we came by it is a story for the ages. But that seems to be the way it's been in any armed force for a long time. After Viking raiders raided villages during the Middle Ages, they would then write their exploits in great sagas that detailed their deeds and combat adventures.
But the problem with that was they didn't have name tapes on their raiding gear. And if they did, a LOT of them would read "OLAF." How do you tell the story of what two (or more) Olafs did on a single Viking raid, when none of them have last names?
Nicknames, of course.
People of all times and periods of history have used nicknames, says Paul Peterson, a who wrote his University of Minnesota doctoral dissertation on Norse nicknames. Even he wrote that the names Norse men had to choose from was small so nicknames became necessary.
Like military nicknames and callsigns, they came from stories of the person in real life or descriptions of the Viking in question – like "Hálfdan the Generous and the Stingy with Food."
But they are a critical piece to the warrior's story and even influence the plot. For example, "Ǫlvir the Friend of Children" earned his nickname because he wouldn't catch children on spears, which was a custom of the time. That could be a critical piece of literary characterization.
Times have definitely changed since "Þórir Leather Neck" earned his nickname. Today, Marines wear that title with pride, but Þórir was being made fun of for the goofy cowhide armor he tried to make.
And then there are the less family-friendly nicknames.
Like you and your buddy who nicknamed someone "Fartbox" and made it stick, the Vikings of yesteryear were no more mature. Names included Kolbeinn Butter Penis, Herjólfr Shriveled Testicle, Skagi the Ruler of Sh*t, and Hlif the Castrator of Horses.
And then there were the badass nicknames like Ásgeirr the Terror of the Norwegians, Þorfinnr the Splitter of Skulls, and Tjǫrvi the Ridiculer.
The Medievalists tells us that the best source for Viking nicknames comes from the saga that details the colonization of Iceland in the 9th and 10th Centuries.