'Vikings' season 4 episode 16 spoilers: Ragnar's sons to take up arms in the aftermath of their father's death

One story's end brought life to a new beginning as the great Viking warrior, Ragnar Lothbrok (Travis Fimmel), succumbed to his death in episode 15 of "Vikings" season 4. With his son, Ivar the Boneless (Alex Høgh) reaching home and learning about his mother Aslaug's (Alyssa Sutherland) death, it seems that the fall of one great man is about to give rise to another.

The last couple of episodes of History's take on Ragnar's saga saw the legendary Viking bonding with his crippled son, Ivar, whom he had entrusted with the most important mission of bringing the news of his death back home to Kattegat. Along the way, Ragnar had been motivating Ivar toward his potential for greatness, and eventually told him in their last moment together that it had always been Ivar whom he believed to be the most important to the future of their people.

The newfound confidence that Ragnar had inspired in his son will lead Ivar to challenge the new queen of Kattegat, Lagertha (Katheryn Winnick), in a single combat in the next episode of "Vikings" season 4. Upon reaching home with news of their father's death, Ivar's brothers, Ubbe (Jordan Patrick Smith) and Sigurd (David Lindström), also told him of their mother's demise at the hands of Lagertha. It seems that before Ivar goes out with his brothers to avenge their father, he will first seek revenge for his mother.

Lagertha knew the risk she was taking when she let Ubbe and Sigurd live, but with Ragnar now dead, and Ivar having gained conviction in his words, the reinstated queen of Kattegat seems to have been shaken enough to want to seek advice from a seer. Will she meet her end at the hands of one of Ragnar's vengeful sons? Or will they all end up working together, if only to avenge Ragnar's death?

In an interview with Variety, series creator Michael Hirst hinted that the infamous Great Heathen Army, which is historically known to have been led by Ivar following his father's death, will start taking form in the next episode of "Vikings."

"Bjorn will return. All the sons will be part of what was called the Great Heathen Army," Hirst said.

"Vikings" season 4 episode 16 will air on Wednesday, Jan. 4, at 9 p.m. EST on History.