Variations: Hrosshvalr, Hrosshualar, Hrosshveli, Rosshvalur, Equinus Cetus, Horse-whale; Saehestur (Sea Horse); Stökkull (Jumper, probably erroneously); Stori Svinhvalur (Large Pig-whale); Pollur (Tenacious One); Monoculus


The Hrosshvalur, or “Horse-whale”, is among the most cruel and dreaded of the Icelandic illhveli, or “Evil Whales”. Only the Stökkull and Raudkembingur rival it in malice. It is irredeemably evil and is unfit for eating, its flesh vanishing from the pot if cooked, and its consumption was banned by law.

The hrosshvalur is easily confused with its fellow illhveli; notably, it has a red crest similar to the raudkembingur, and tends to jump onto ships like the stökkull. It is distinguished from those two by its enormous eyes, which have earned it the nickname of Monoculus (“One-Eyed”). It earned its name from a somewhat equine head, a flowing red mane covering more or less of its neck, a horse’s tail, and a call like a horse neighing. It also smells bad, is covered with fine fur, and its insides are like those of a horse. Jon Gudmundsson, who confused it with the stökkull, depicted it with a dappled back. These whales grow 30 to 80 cubits (15 to 40 meters) long.

As with other illhveli, the hrosshvalur delights in destroying ships. A hrosshvalur will charge over the waves at high speed, holding its head just above the water with its mane trailing behind. These whales sink ships by jumping onto them, or pressing their weight on them until they capsize. Horse-whales are also portents of bad weather, and can create huge waves by whipping their tails. A number of euphemistic names are used to refer to horse-whales, to avoid attracting their attention. While not as easily distractable as raudkembingurs and stökkulls, their large eyes are a notable weakness.

In the 13th century, a hrosshvalur that surfaced alongside a ship was bombarded with every heavy implement available, which caused it to sink back below the waves. Another hrosshvalur attacked the heroes Hjalmper and Olvir; it was defeated with the help of a Skeljungur (“shell whale”), vagnhvalur (“chariot whale”, or killer whale), and two vultures. A cutlass thrown into one of its large eyes weakened it significantly, and it was torn apart by the whales.

Hrosshvalurs are also associated with the dark arts. The size and ferocity of the horse-whale made it an excellent accomplice for sorcerers and witches bent on destruction, and a perfect form to assume when causing chaos. In the Kormaks saga, the witch Dorveig transforms herself into a hrosshvalur to attack the brothers Kormakr and Dorgils. They recognize her from her eyes, and drive her off by throwing a javelin into her back.

It is generally believed that the hrosshvalur was derived from the walrus, and ultimately gave it its name by converting hval-hross to walrus. However, it was clear early on that it and the walrus were very different animals, as Gudmundsson separately describes both the hrosshvalur and the walrus (rostungur) in detail. Another possibility would be the giant squid, which would have contributed the large eyes and a mane of tentacles.


Davidsson, O. (1900) The Folk-lore of Icelandic Fishes. The Scottish Review, October, pp. 312-332.

Dillmann, F. Les Yeux de Dorveig: À propos de la métamorphose en hrosshvalr d’une sorcière de la Kormaks saga. In Heizmann, W. and van Nahl, A. (2003) Runica – Germanica – Medievalia. Walter de Gruyter, Berlin.

Fraser, F. C. An Early 17th Century Record of the Californian Grey Whale in Icelandic Waters. In Pilleri, G. (1970) Investigations on Cetacea, vol. II. Benteli AG, Bern.

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