Verence I
Murdered by Duke Felmet, his ghost haunted Lancre Castle until his presumed son Tomjon returned to claim the throne.
He was said to be a womaniser, and people assume Verence II is a result of a nightly adventure with the Fool's mother. Unfortunately for him, it isn't, but that doesn't really matter as the people of Lancre don't really care who their king is, as long as he does his job and doesn't bother people too much. He apparently had quite the body, liked big dogs, and lived life fully, one bit at a time. See Wyrd Sisters for details.
He enjoyed exercising his droit de seigneur, and, although a lot of the characters seem to be under the impression that it is actually a large, shaggy dog, it actually translates as 'Lord's Right'. What this actually allows is (thankfully) lost in the mists of time.
Annotation
He can be seen as similar to the ghost of Hamlet's father in the Shakespeare play, Hamlet.