Marcus Cunomorus

Mark of Cornwall (Latin Marcus, Cornish Margh, Welsh March, Breton Marc'h) was a king of Kernow (Cornwall) in the early 6th century. He is most famous for his appearance in Arthurian legend as the uncle of Tristan and husband of Iseult, who engage in a secret affair.

Mark sent Tristan as his proxy to fetch his young bride, the Princess Iseult, from Ireland. Tristan and Iseult fall in love, and, with the help of a magic potion, proceed to have one of the stormiest love affairs in medieval literature. Mark suspects the affair and eventually his suspicions are confirmed. In some versions, he sends for Tristan to be hanged, and banishes Iseult to a leper colony. Tristan escapes the hanging and rescues Mark's bride from her confinement, later to be discovered by Mark. Mark eventually forgives them, with Iseult returning to Mark and Tristan leaving the country.

The story is cyclical with Mark suspecting Tristan and Iseult of adultery and then believing they were innocent. This happened again and again in the story. In the Beroul version, Tristan and Iseult are never in grave danger due to the narrator's declaration that he himself and God were on their side. King Mark, in the role of husband, is not portrayed as idealistic as other kings in Arthurian literature who were only portrayed in the role of king and not the personal role of husband.

In the Prose Tristan, Mark's character deteriorates from a sympathetic cuckold to a downright villain. He rapes his niece and then murders her when she produces his son, Meraugis. He murders his brother Baldwin as well. In earlier versions of the story, Tristan dies in Brittany, far away from Mark; but in the Prose Tristan, Mark stabs Tristan while he plays the harp under a tree for Iseult. Though this version of Mark's character was popular in other medieval works, including the Romance of Palamedes and Sir Thomas Malory's Le Morte d'Arthur, modern versions of the Tristan and Iseult legend tend to take their inspiration from the older poetic material, and Mark becomes a sympathetic character once again. In these legends, Mark is usually seen as ruling Cornwall from Tintagel Castle.

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