Ari was the second son of King Horik. As the son of a king, Ari was a Buthlungr, or 'Prince' of Denmark.
Upon their arrival at Kattegat, King Horik had gushed about his sons. At the feast Earl Ragnar hosted in their honor, Ragnar spoke to him of his own son, Bjorn, whom Ari expressed interest in meeting. Their upcoming raid to the West is his first, so he is eager to prove himself in battle and make his father proud.
When they reach Wessex, the Northmen decide to rest by a forest stream when they are spotted by soldiers who initiated a stealth attack. Ari was the first casualty, struck with an arrow. Needing to face their enemies, King Horik and Erlendur were at first unable to tend to him. In the beginning of the battle, when both sides were waiting for the other to strike, Ari's cries of pain could be heard. In the aftermath of the battle, Horik and Erlendur are seen mourning the dead Ari.
|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|