|Portrayed by Faolán Pelleschi|
|Full name:||Sigurd Ragnarsson|
|Parents:|| Ragnar Lothbrok (father)|
|Siblings:|| Bjorn (half-brother)|
Gyda † (half-sister)
|Relatives:|| Rollo (uncle)|
Sigurd "Snake-in-the-Eye" is the third son of Ragnar and Aslaug. Through Ragnar, Sigurd is descended from the Volsungr (descendents of Odin through his great-grandson Volsung) and the Ynglings (descendents of Frey) through his mother.
Aslaug had prophesized that he would be born with the image of the serpent-dragon Fafnir in his eye, the same one her father Sigurd killed. When he was born so, Aslaug named him "Sigurd Snake-in-the-eye" after her father and because of the mark on her son's eye.
- In the prophecy of the the Seer on children of Ragnar, Sigurd is the son marry the daughter of a king. In fact he married Blaeja, the daughter of king Aelle of Northumbria and they Had the Children Harthacanute and Aslaug, who was named after her grandmother Aslaug.
- As of the Season 2 finale, Sigurd and his brothers would be known by the Old Norse title of Budlungr or 'prince'.
- Sigurd Ormr i Auga (Snake-in-the-Eye) would eventually inherit and rule over the island of Sjaelland in Denmark, Viken in southern Norway and the lands of Halland and Scania in southern Sweden. He was also the ancestor of a line of Danish kings such as Harthacanute, Gorm the Old, Sweyn Forkbeard and Canute the Great.
- Sigurd is likely named for both Sigurd Hring (Ragnar Lothbrok's father) and Sigurd the Dragonslayer (Aslaug's father).
|Season two appearances|
|Brother's War||Invasion||Treachery||Eye For an Eye||Answers in Blood|
|Unforgiven||Blood Eagle||Boneless||The Choice||The Lord's Prayer|
|Season three appearances|
|Mercenary||The Wanderer||Warrior's Fate||Scarred||The Usurper|
|Born Again||Paris||To the Gates!||Breaking Point||The Dead|