The twelfth century Anglo-Norman chronicler Geoffrey Gaimar records in his verse history of the English (Lestorie des Engles ), the assassination of the English king Edward the Martyr (r. 975-78), allegedly lured to his death by his dwarf who clearly had the entertaining skills of the jester:
He had a dwarf named Wolstanet
Who could dance and play.
He could leap and pipe,
And play many other tricks.
The king saw him, called him,
And ordered him to play.
The dwarf said he would not,
He would not play at his order.
Regarding the dwarf’s luring the king to his death, I have so far found no other reference to either Wolstanet or his alleged dastardly deed. For now, I would park him in the ‘maybe’ department pending something else to corroborate his existence.
Source: Geoffrey Gaimar (fl. c. 1130s), Lestorie des Engles (ll. 3991-98), ed. by T.D. Hardy and C.T. Martin (Rolls Series: 1889).
Image credit: Miniature of Edward the Martyr, Genealogical roll of the kings of England; British Library, MS Royal 14 B VI.