I’m having trouble tracking down an authoritative historical source on this, but I’ve seen it mentioned in numerous places that in ancient Irish society – in which poets were held in especially high esteem – it was supposedly possible to compose a poetical satire against someone, such that it raised boils on the face of its target. Supposedly, if the target were a king, this physical deformity would thus make them unfit to rule.

“In legal terms, the satire was considered an assault, and so could not be tossed about lightly on a whim. If a satire was found to be unjust and insulting, ie, it called someone names, or if it mocked their physical appearance, the poet had to pay compensation in the form of an honour price, or eric.And of course, the higher the accused’s status, the higher the fine. Legally, a satire had to be based on truth…

And (same source):

Believe it or not, the satire fell into ten categories, the most scalding of which was known as the Glám Dicenn. You want boils on the face of your wicked evil King? Then, this is the satire for you.

The glám dicenn, when raised by a powerful poet, could cause ‘the Three Blisters of Satire’ to appear on the face of the victim, thus marking his shame and dishonour for all to see.

There seems to be some corroboration of the above here in The Encyclopedia of Celtic Mythology and Folklore By Patricia Monaghan, whose wording is so similar to the above blog post that it may be their original source.

Anyway, there’s a lot to unpack here, but just wanted to bookmark all of this…