Long before Sergio Aragonés filled the margins of MAD Magazine with tiny, weird cartoons, the margins of medieval manuscripts were a playground for bored monks with crude senses of humor.
While some monks expressed themselves with flat-out crudity, a more common motif was the ubiquitous, triumphant armed rabbit, often shown killing dogs, humans, and other enemies of bunnykind.
Writer Jon Kaneko-James explains the symbolism of these murdering coneys, illustrated with fine examples of the form.
Since rabbits and hares were signs of cowardice, innocence, helplessness, and passive but willing sexuality (lots of medieval sexual imagery involves wolves jumping on rabbits), the idea of them getting their revenge amused medieval artists as much as it amuses me. All told, they are pretty helpless animals whose only hope of survival is to breed fast and run away, a trait that wasn't particularly successful in the Medieval era – a significant proportion of the French economy was based on eating and skinning rabbits.
The image of the rabbit's revenge transcends just the illuminated manuscript – the misericord seats in Manchester Cathedral are supported by a 15th century carving of a hunter being spitroasted by rabbits while his dogs are boiled in the pot.
In medieval manuscripts the image of the rabbit's revenge is often used to show the cowardice or stupidity of the person illustrated. We see this in the Middle English nickname Stickhare, a name for cowards, and if the we take a look at the Poke list, we'll see a lot of tough hunters cowering in the face of rabbits with big sticks. In the 13th century epic Roman de Renart we even have the character Coward, who is a hare, capturing an armed man who drops his sword at the sight of him and ends up being dangled from a stick.
Why Are There Violent Rabbits In The Margins Of Medieval Manuscripts? [Jon Kaneko-James]