For example, cutting off a horse's tail was a great way to insult a knight because of the status that came with owning a horse.
The book "Sveriges historia 600-1350", page 295, there's a list of illegal names to call someone; tikvalp, fegis, trollkona, hortuta, förgörerska, tjuv, sköka, hora, rövare, mördare, niding, träl, kasevarg (mordbrännare), agnabak (spannmålstjuv), skökoson, lögnare, son av hynda.
Translation to the beat of my ability as a native Swede:
Female puppy, coward, female magician, woman with questionable character, destroyer (female), thief, prostitute, whore, robber, murderer, executioner's assistant, slave, arsonist, grain thief, son of whore, liar, son of bitch.