Vikings are the primary characters of the How to Train Your Dragon book and film series. They reside in the northern seas where they pirate, loot, steal, raid, etc. They typically dress in animal pelts, fur boots, and horned helmets and possess a great amount of knowledge on navigation, thievery, and combat. Their tempers are also generally foul and stubborn, and they rarely communicate with people from outside of their tribes on a regular basis. The feature that most greatly separates them from real-life Vikings are their use of dragons as partners or pets. They also are separated from real Vikings is the horns on their helmets and the fact that they fight Romans in the books. The Roman Empire had fallen by the time of the first Viking raids in real life.
There are several known tribes of Vikings in the book series, including the Hairy Hooligans, the Merciless Meatheads, the Hysterics, and the Bog-Burglars. The first two are known to get together during the initial Viking tests their youth must pass in order for they and their dragon partners to be recognized by their respective villages. The Hysterics are the black sheep of the Vikings in that they seem to be feared by all other Viking tribes for their insanity and relative barbarism. The Bog-Burglars comprise primarily female Vikings who are as foul and sturdy as any other.
Hairy Hooligans: The main Viking Tribe in the books, who live on the Isle of Berk. Their present chief is Stoick the Vast and the heir of the tribe is Hiccup Horrendous Haddock III. Also, they have a Pirate Training Program for the teenagers of the tribe, which is run by Gobber the Belch.
Meatheads: The closely neighboring tribe to the Hairy Hooligans. Not much is known about this tribe except their present chief is Mogadon and the heir of the tribe is Thuggory.
Bog-Burglars: The tribe filled with mostly fierce female Vikings. Like their name said they are amazing burglars and are often competing against the Hairy Hooligans. Their present chief is Big-Boobied Bertha and the heir of the tribe is Camicazi.
Hysterics: This tribe is the most feared of all for their insanity and relative barbarism. The tribe believes that the earth is round and there is a place called America. This is ironic since they were right. They were once trapped on their island for 15 years by the Doomfang until Hiccup fed him the Potato. Their present chief is Norbert the Nutjob.
Outcasts: The tribe of savage Vikings that always constant war with other tribes. Their chief was once Alvin the Treacherous (who was exiled because he got bold) and is a distant relative of the Hairy Hooligan's royal blood line.
Lava Louts: The tribe that is the worst enemy of the Hairy Hooligans that live on an island with a volcano. Not much is known about this tribe except they wear fireproof suits created by dragon skin.
Though their lives as Vikings are emphasized in the film adaptation, the individual tribes are not mentioned at all. The Vikings are also revised to be mainly dragon killers and do not begin to accept dragons into their lives until the end of the first film.
Hooligans: Primarily living on the Isle of Berk, the Hooligans have thrived for seven generations. At the start of the franchise, their chief is Stoick The Vast, a strong and hefty Viking, towering over 7 feet tall, who rules with both an iron fist and compassion for his people. After the unfortunate event of his death in the second movie, his only son, Hiccup Haddock III, rises to the chieftain throne, and continues his life passion to create a utopia for both dragons and humans.
Outcasts: Ruled by Alvin the Treacherous, the Outcasts are a barbaric tribe of outcasts from other tribes, Alvin himself being a former Hooligan, having been banished by Stoick the Vast many years earlier. They reside on Outcast Island, capturing and attempting to use dragons for their own treacherous purposes. They've been long time enemies of the Hooligans, however Alvin and Stoick made amends half way through the TV series. Though technically allies with the Hooligans now, the Outcast tribe as a whole appear to still be rough and barbaric.
Berserks: Despite their name, their chief is the peaceful Oswald the Agreeable, and have been friends with the Hooligans for 50 years. But when Oswald disappears and is presumed dead, his only son Dagur the Deranged ascends to the position, and he lives up to the "berserk" name. He wages war on Hiccup Haddock III and the rest of the Hooligan Tribe in an effort to get the dragons he's trained. After joining up with Dragon Hunters however, he has a change of heart, reunites with his sister Heather, and the Berserkers become strong allies to the Hooligans. Dagur and Heather go searching for their father and peacefully take charge of the tribe on Berserker Island.
- Hiccup Haddock III
- Astrid Hofferson
- Ruffnut Thorston
- Tuffnut Thorston
- Fishlegs Ingerman
- Snotlout Jorgenson
- Stoick the Vast
- Gobber the Belch
- Spitelout Jorgenson
- Finn Hofferson
- Phlegma the Fierce
- Hoark the Haggard
- Gustav Larson
- Silent Sven
- Alvin The Treacherous
- Oswald the Agreeable
- Dagur the Deranged
- Gruffnut Thorston
- Burnthair the Broad
- While almost every Viking in the franchise and the book series has a helmet with horns on it, in history, Vikings would almost never wear horned helmets.