Warning: Spoilers for the Season 5B premiere of Vikings lie ahead.
The father of all bombshells landed in the lap of Bjorn "Ironside" Ragnarrson in the midseason premiere. After a lot of subtle hints throughout Vikings' run, Rollo confronted Lagertha about Bjorn's paternity, asserting he is actually Bjorn's biological father. Not Rollo's brother Ragnar.
For his part, Bjorn was having none of it. He pointed to his physical resemblance to Ragnar as one of the many reasons he is Ragnar's biological son. Bjorn certainly has a point, although he could have just favored his mother.
Whether he genuinely believes this in his heart is unclear. He certainly gave a sound mental argument for denying Rollo's paternity assertion. Can somebody please get a DNA test, stat? If only they were around back in their day, then we could learn the hard truth for sure.
Potentially blocking Bjorn from believing it is that he detests Rollo for betraying their people. Bjorn is much more favorable to Ragnar. Despite a strain in their relationship when he was younger, they managed to repair things later on. The groundwork for the paternity twist has been laid out for years though.
Suffice it to say that every episode had been leading to the scene in the Season 5B premiere. In an interview with ET, actor Clive Standen revealed that he has been playing the angle that Rollo may be Bjorn's biological father, all along. Yes, all along. Standen shared:
Clive Standen has always done a fantastic job playing Rollo's interactions with Lagertha and Bjorn. So, it has been natural to suspect Season 5B's revelation regarding Bjorn. Making it not entirely surprising, but rather the much-anticipated and welcome culmination of something long in the works.
The actor went on to mention the scene from Season 3 when Bjorn nearly dies in Paris. Clive Standen said that he played that scene with a sense of "fatherly control." His work paid off as Bjorn's paternity has remained a lingering and unspoken mystery throughout Vikings. Discussing the journey to get here, Standen said:
A deleted scene from a previous season of Vikings seemed to address it in a veiled sense. Even Bjorn admits he was familiar with the rumors during the trio's "family meeting" in the midseason premiere. As for Lagertha, she never seemed to return Rollo's forlorn romantic gazes. She apparently moved on from Rollo without ever looking back.
Now, the question becomes what the confirmation of Bjorn's potential paternity may have on him. He has been willed through many things in his life using the "fact" that he is Ragnar's son. Ragnar was a man he pretty much idolizes, not only because he is his father, but because of who he represents to Bjorn. Rollo signifies the exact opposite of who he wants to be.
At least, we now know the real motive behind Rollo backing Ivar. It was apparently in the hopes of pushing Lagertha, and arguably more so Bjorn, into joining him in Frankia. So, Rollo betrayed them for what was essentially a larger picture. Backing the enemy of your maybe son's mother is not exactly the best way to ingratiate yourself with your maybe son, just saying.