I've been trying to think of a word recently, I'm sure I once knew it. It's a term for a sub-category of epithet, a way of summarising character – it describes the 'Bold' in 'Charles the Bold' - a sort of permanent adjective that can forever remind us just how completely unprepared Ethelred was.
As a boy I was dismayed to discover that my royal namesake, a king of England who ruled from 1135 to 1154, is known to history as Stephen the Irresolute. The John Player cigarette card in my dad's “The Kings and Queens of England” album twisted the knife; “the so-called reign of Stephen was one of the most miserable in English history”. Hmph.
Kings and notorious criminals (sometimes one and the same) seem to attract this kind of epithet. I suppose for most of us our anonymity outweighs our notoriety, at least historically, so our character traits don't become permanently attached to our name. I remember, in a factory I once worked in, being mystified as to why a pasty-faced fellow was known as Black Dennis. One lunch-break, not so much out of curiosity or altruism as due to a shortage of seating, I joined him at his otherwise deserted table. Without preamble and with a practised deliberation Black Dennis shared with me his bleak reflections on man's lot - and, in a canteen bathed elsewhere in florescent light, I was soon enveloped in an inky gloom so opaque that only the smell of congealing grease betrayed the whereabouts of my bacon sandwich.