The Horrendous Haddocks were a family of Vikings from the Hairy Hoolighan Tribe. They were by far the most prominent family in the Barbaric Archipelago, with many members having "forever altered the course of history."
The first known Horrendous Haddock was Hiccup Horrendous Haddock I. Hiccup the First ended the First Dragon War by threatning to use the awful power of the Dragon Jewel after being given it by his new dragon companion, the Wodensfang. Hiccup the First then became blood-brothers with the Wodensfang, and the first King of the Wilderwest after putting the first Dragonmark upon his forhead, swearing to never use the Dragon Jewel for evil.
- Hiccup Horrendous Haddock I
- Grimbeard the Ghastly
- Hiccup Horrendous Haddock II
- Stoick the Vast
- Valhallarama (through marriage)
- Hiccup Horrendous Haddock III