Of all the illhveli, wicked whales, that plagued Icelandic waters in ancient times, the Raudkembingur, the Red Crested Whale, was the most savage and bloodthirsty. It may not had the size or raw power of some of the other illhveli, but its ferocity and determination to hunt and harm boats was unmatched by any other living creature in the sea.
The raudkembingur is an abomination, and eating its inedible flesh is not only deadly but forbidden. Those desperate enough to try, came to discover that boiling its meat causes it to disappear from the pot.
The nature of the red crest that gives the raudkembingur its name is unclear. Some witnesses' accounts refer to a crest of bristly hair, others to a mane like that of a horse, and some other talk of a row of small fins moving like sea-snakes. The length of the crest also varies from account to account. For instance, in his "On Iceland's Distinct Nature," Jón Ólafsson, the Icelandic scholar, mentions that "the crest is bright red, obvious on the beast's brown body." Other, more recent, accounts mention that the crest extends along the entire dorsal section of the animal, and it's red all over, but not as red as the head of the creature.
Body-wise, the whale's elongate, hydrodynamic shape makes for a fast swimmer. The fastest of all the illhveli. As they move, their position underwater is given away by the massive amounts of bubles formed as the water passes through the red crest.
As mentioned before, there is no limit to the malice of the raudkembingur. The oldest accounts, recovered from oral tradition from before the 16th Century, associate this creature with the evil, chaotic forces residing in the northernmost frozen wastelands. Within Scandinavian waters, its presence was enough to dissuade fishermen from an area. So, it is said, the evil masters send the raudkembingur ahead of themselves, to scare the fish and the fishermen, so they can carry on with their villainous machinations unseen. Throughout the middle ages, the reputation of this whale only grew. Ultimately, it became the only marine beast mentioned in the Danish Demonology, written by Vicar Hans Lauridsen (1596).
Raudkembingur were known for their trickery. They could play dead, floating on the surface of the water belly-up for a full fortnight, until someone was foolish enough to approach it. And once a boat was within range, they would leap onto the vessel, putting its teeth to use by destroying the hull and drowning all aboard. Much like a shark is followed by pilot-fish, the raudkembingur may be followed by beluga whales or narwhals, who eat the spoils of the hunt while offering camouflage to the "red crest."
As with many mythical beast, the strength of this monster is often the only way to defeat it. As such, out at sea, the best hope of foiling a raudkembingur is the whale’s obsession for destruction. Because, once a boat escapes it, if it does not manages to destroy another within the same day, it will die of frustration.
Raudkembingurs will also overexert to death when pursuing prey. A boat captained by Eyvindur Jónsson off Fljót (northern Iceland) ran into a raudkembingur. Panicked, the crewmen rowed for land as fast as possible until they reached safety at the inlet of Saudanesvik. The sea then turned red as the raudkembingur inhaled its last breath. After the escape, the boat was nickname of Hafrenningur (Ocean Runner).
The demonic raudkembingur is also associated with sorcery and metamorphoses. One tale tells of a callous young man at Hvalsnes (a town known for its alluring landscapes) who was cursed by the elves (a local Ellerwoman was suspected) into becoming a monstrous red-headed whale. He wreaked havoc in Faxafjord and Hvalfjordur, until he tried to chase a priest up-river. The red-head died of exhaustion in Hvalvatn Lake (its bones, transfixed into rock) can still be seen near the edge of the water.
-Guðrún Bjarkadóttir. 2010. Icelandic mammal name: Their history and origins, Master Thesis. University of Iceland. Department of Icelandic Studies and Culture.
-Jón Baldur Hlíðberg, Sigurður Ægisson. 2008. Meeting with Monsters: An Illustrated Guide to the Beasts of Iceland. JPV.