Vikings fans are well-aware that Season 5B is going to present a fresh dose of Rollo. So, what exactly do we owe to his homecoming? Publicly, it is for the sake of political advancement. However, Vikings' creator Michael Hirst hinted at Rollo's real and unexpected motivation, saying:
That's right, his relationship with his former sister-in-law is one of Rollo's true motives. What makes Michael Hirst's Vikings reveal to TV Guide all the more compelling is that it teases something below the surface. He talks of "unfinished business" between Rollo and Lagertha. What could that possibly entail?
Rollo had seemed to pine for Lagertha when she was and was not his brother's wife. However, that ship seemed to sail long ago. Rollo married Princess Gisla, and Lagertha has found a serious new relationship. The latter romance will apparently be key in Season 5B.
Perhaps, he is trying to resolve the past. There has always been a hint at a backstory of a romantic triangle that brought added turbulence to the rivalry between the brothers. It is not entirely clear what went on between Lagertha and Rollo before Vikings began.
It is an aspect that has led to speculation regarding Bjorn's paternity. Vikings' creator previously hinted at the paternity plot twist in an interview with IGN. In it, Michael Hirst told of stories hinted at in Season 1, including who Bjorn's father actually is.
Is that the "unfinished business" Rollo wants to deal with? It would make sense. It would be very different from his public goal of political inroads. Rollo inquiring about Bjorn's paternity would be as personal and private an issue as Vikings' creator hints that Rollo's is.
There has always been room for this speculation. Bjorn and his uncle share their temperaments in common. Lagertha's son has always possessed an underlying warmth that Rollo has similarly exhibited. Whereas, Ragnar's disposition always belied a certain coldness and practicality.
Elsewhere in the earlier mentioned story, Michael Hirst is quoted as saying that Lagertha will have to face "hard truths" regarding Rollo and her ambition. Did her aspirations to be the wife of a man, as obviously destined for power in Kattegat as Ragnar, come at Rollo's expense? As in denying him his biological son? That would be a hard truth.
All of the puzzle pieces seem to line up with this storyline coming into play in Season 5B. Whether the show actually does, will be interesting to learn. So, while we have a big piece of the puzzle, Rollo's full motivation remains a mystery for now.
It seems like Vikings has been building towards this storyline for a while. After five-and-a-half seasons, one can only hope the connection between Rollo, Lagertha, and Bjorn will finally be addressed.