A leviathan is a type of enormous whale, usually grey in color but sometimes white. They are described as the oldest and largest creatures living in the entire world, implying they surpass even dragons in size.
According to ironborn legend, Nagga, the first sea dragon, was big enough to feed on krakens and leviathans. A black leviathan is included in the sigil of House Volmark of the Iron Islands. The longship Leviathan is part of the Iron Fleet. Aeron Greyjoy mentions that the Drowned God speaks the language of leviathan.
Ibbenese whaling ships are renowned for their strength, as they are built to weather any storm and withstand the assaults of even the largest leviathans. The whalers hunt leviathans at Leviathan Sound and elsewhere in the Shivering Sea. The bone, blubber, and oil of the whales they hunt are Ib's chief trade goods, and have made the Port of Ibben the largest and richest city of the Shivering Sea.
In 56 AC, when planning to travel west of Westeros to discover new lands, Alys Westhill chose to avoid the northern Sunset Sea and its many dangers, including island-sized leviathans, and decided on a more southerly route for the journey of her Sun Chaser.
Around 58 AC, while returning to Oldtown from accompanying Alys Westhill's journey in the Sunset Sea, Ser Eustace Hightower's Lady Meredith encountered a pod of leviathans. One of them, a huge white bull larger than a ship, deliberately slammed into the Lady Meredith and cracked her hull. Eustace redirected for the Summer Isles, but was further south than he realized, and the ship ended up in Sothoryos.
A Feast for Crows
A Dance with Dragons
A fisherman may hook a grey leviathan, but it will drag him down to death unless he cuts it loose.
Behind the Scenes
In the real world, the Leviathan is a legendary sea serpent from the Bible, whose name came to be used as a term for great whales and other sea monsters, as well as a genus of prehistoric whales. Additionally, the white bull leviathan encountered by the Lady Meredith may be a reference to Herman Melville's novel Moby-Dick.
- A Feast for Crows, Chapter 45, Samwell V.
- Fire & Blood, The Long Reign - Jaehaerys and Alysanne: Policy, Progeny, and Pain.
- The World of Ice & Fire, Beyond the Free Cities: The Shivering Sea.
- A Feast for Crows, Chapter 19, The Drowned Man.
- The World of Ice & Fire, The Iron Islands: Driftwood Crowns.
- Fire & Blood, Jaehaerys and Alysanne - Their Triumphs and Tragedies.
- The World of Ice & Fire, The Free Cities: Lorath.
- The World of Ice & Fire, Beyond the Free Cities: East of Ib.
- A Feast for Crows, Chapter 11, The Kraken's Daughter.
- A Dance with Dragons, Chapter 56, The Iron Suitor.
- A Feast for Crows, Chapter 1, The Prophet.
- The World of Ice & Fire, Beyond the Free Cities: Ib.
- A Dance with Dragons, Chapter 15, Davos II.
- A Dance with Dragons, Chapter 47, Tyrion X.
- A Feast for Crows, Chapter 18, The Iron Captain.