https://en.wikipedia.org/wiki/Flyting

Flyting is a ritual, poetic exchange of insults practiced mainly between the 5th and 16th centuries. Examples of flyting are found throughout Scots, Ancient, Medieval[8][9] and Modern Celtic, Old English, Middle English and Norse literature involving both historical and mythological figures. The exchanges would become extremely provocative, often involving accusations of cowardice or sexual perversion.

In the confrontation of Beowulf and Unferð in the poem Beowulf, flytings were used as either a prelude to battle or as a form of combat in their own right.[11]

In Anglo-Saxon England, flyting would take place in a feasting hall. The winner would be decided by the reactions of those watching the exchange. The winner would drink a large cup of beer or mead in victory, then invite the loser to drink as well.[12]

Flyting became public entertainment in Scotland in the 15th and 16th centuries, when makars would engage in verbal contests of provocative, often sexual and scatological but highly poetic abuse.

This makes me wonder if it's possible that modern battle rap is a direct descendant of medieval flyting, or if this a case of convergent cultural "evolution" where two very similar practices arose without any apparent connection.

@PugJesus Capaldi did it quite well (OK, not quite Viking, but similar era) as The Doctor. youtube.com/watch?v=qwoWo4ChYuQ