The fate of the Kattegat throne will be determined when "Vikings" returns from its mid-season hiatus for season 4.

At the end of the first half of the season, the loss to Paris during the Vikings' big raid made Ragnar Lothbrok (Travis Fimmel) retreat to an unknown land and abandon his post as the King of Kattegat for a long time.

But Ragnar's return to his homeland was resented by his young sons with Aslaug (Alyssa Sutherland), who had all grown up to become young men with different strengths and weaknesses.

The midseason finale episode introduced Jordan Patrick Smith as Ubbe, the eldest son of Ragnar and Aslaug. The second son named Hvitserk is portrayed by Marco Ilsø. David Lindström portrays the role of Sigurd, also known as Snake-in-the-Eye. They are joined by Alex Høgh Andersen as Ivar The Boneless, the fourth and youngest son of the Kattegat royalties.

While Ragnar's sons all have their desires to take over the Viking leadership from their father, reports claim that Ivar The Boneless could cause the most damage to the king of Denmark.

"The thing which separates Ivar from the other brothers is he understands Ragnar and he does not respect him in the same way as the other brothers," Andersen told IGN. "He's making fun of him. He's a little bit like Ragnar is to everybody else, and for once Ragnar experiences someone like him toward him. It's pretty new and interesting."

The other three actors also believe that Ivar could be the most cunning among the all the sons of Ragnar.

"Even though he's the younger brother, we would look up to him for the Viking he is and how strong-willed he is," Smith stated. "He has one of the biggest disabilities you can have as a Viking where you can't walk, but he's still smart enough and strong enough to keep going."

History Channel has yet to announce the official air date of the midseason premiere episode of "Vikings" season 4.