Keelhauling

Keelhauling (Dutch kielhalen; "to drag along the keel"; German Kielholen; Swedish kölhalning; Danish kølhaling; Norwegian kjølhaling) is a form of punishment meted out to sailors at sea. The sailor was tied to a line that is looped beneath the vessel, thrown overboard on one side of the ship, and dragged under the ship's keel, either from one side of the ship to the other, or the length of the ship (from bow to stern).

The common supposition is that keelhauling amounted to a sentence of either death by extreme torture, or minimally a physical trauma likely to permanently maim. The hull of the ship was usually covered in barnacles and other marine growth, and thus keelhauling would typically result in serious cuts, loss of limbs and even decapitation. If the victim was dragged slowly, his weight might lower him sufficiently to miss the barnacles, but this method would frequently result in his drowning. There was also a risk of head trauma, especially if the ship was in motion.

There is limited evidence that keelhauling in this form was used by pirate ships, especially in the ancient world. The earliest known mention of keelhauling is from the Greeks in the Rhodian Maritime Code (Lex Rhodia), of c. 800 BC, which outlines punishment for piracy. There is an image on a Greek vase, for example, from the same era.

Several 17th century English writers such as Monson and Boteler recorded the use of keel-hauling on English naval sailing ships. However, their references are vague and provide no date. There seems to be no record of it in English ship's logs of the era, and naval historian Nicholas Rodger has stated he knows of no firm evidence that it ever happened.

It was an official, though rare, punishment in the Dutch navy, as shown in the painting The keel-hauling of the ship's surgeon of Admiral Jan van Nes. This shows a large crowd gathered to watch the event, as though it was a "show" punishment intended to frighten other potential offenders, as was flogging round the fleet. A contemporary description suggests it was not intended to be fatal.

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