The kraken is a comparatively late and comparatively documentary monster. It enters print through eighteenth-century Norwegian description, above all the Natural History of Norway (1752-53) of Bishop Erik Pontoppidan, which presents it as a real animal of enormous extent, an island-sized creature whose back sailors mistake for land and whose descent drags down ships in a whirlpool. Older Norse references to a hafgufa ("sea-mist") lie behind it.
In the nineteenth century Alfred, Lord Tennyson gave it its literary form in the sonnet "The Kraken" (1830), and Jules Verne and later writers fixed the image of a ship-crushing tentacled beast. The modern reinterpretation is zoological: the discovery, and eventual filming, of the giant squid (Architeuthis) and the larger colossal squid gave the legend a plausible natural kernel, and the kraken is now routinely explained as an exaggerated report of real deep-sea cephalopods, an explanation that fits the tentacled version but postdates, and partly reshaped, the island-sized animal that Pontoppidan actually described.