In Victor Hugo's book, The Toilers of the Sea, the hero Gilliatt is attacked by a giant octopus off the coast of the island of Jersey. And in 1922, some fishermen near the same island reported being attacked by an octopus which nearly capsized their boat before they fought it off in the battle gloriously depicted here.
We posited that encounters such as this might account for the "200 apparently truthful accounts by mariners of the sighting of huge sea serpents." We also wrote that the fishermen's alleged encounter "is held to set at rest the scoffing comments of some naturalists concerning the plausibility of Victor Hugo's celebrated story," though we're not certain quite how.
Read the full story in Sailors' Battle With Huge Octopus Revives Tales Of Dread Sea Monsters