I have a ballad on the death of Thomas Becket on my website.

A lot of ballads seem to have started out as pieces of saga-length narratives, and in older ballads about killings the protagonists are either deities, royalty or proxies for warring polities. The idea that you might want to democratize death and make songs about ordinary people killing each other for purely personal reasons seems to be an early-modern idea.

Pitcairne's collection of criminal trial reports, "Ancient Criminal Trials of Scotland", makes for an illuminating comparison. Centuries of landed thugs conducting vendettas until the law couldn't tolerate the number of rapes, arsons and psychopathic killings they carried out. It's a brilliant piece of gutter journalism much like the true-crime and society gossip mags you see on supermarket shelves - and that was what the ballads of murder and feuding we now have were about. There probably were fair number of killings involving tenant farmers and donestic servants, but it was the elite thugs with family crests who got high-profile trials, ballads and beheadings.