[Warning: This post contains spoilers about the latest episode of Vikings. Read at your own risk!]

For years, Vikings fans have speculated that Ragnar (Travis Fimmel) wasn't actually the father of Bjorn (Alexander Ludwig) and that instead it was his brother Rollo (Clive Standen) who fathered the child with Lagertha (Katheryn Winnick). Welp, for once the conspiracy theorists were correct. The midseason premiere of Vikings pretty much confirmed that long-standing theory in an emotional Lothbrok family showdown.

Rollo had returned to Kattegatt following Lagertha's loss to Ivar (Alex Høgh), a defeat he helped bring to fruition when he sent Ivar his army on the condition that Bjorn not be killed. At the time, this just seemed like Rollo protecting his favorite nephew, but now we know the reason goes much deeper than that. While Rollo told Ivar that he had arrived at his hometown to set up a trade deal between their kingdoms (a very one-sided deal at that), he really returned to help get his former love Lagertha and his son — yes, his son — Bjorn to safety.

As for why this reveal is coming now, five-and-a-half seasons into the series, creator Michael Hirst told us that this is in large part thanks to the repeated requests by Standen, who had always believed that Rollo was Bjorn's true father. "It was something that was driving Rollo and Clive kept asking me about that. He said, 'I have to tell the audience, I have to tell the audience that at least that's my belief,'" Hirst explained.

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When Rollo tracked down Bjorn and Lagertha to share an offer of safe passage for them back to Frankia, Lagertha asked why he would do this given his allegiance with Ivar. "You know I have always loved you, Lagertha, and that Bjorn is my son," Rollo declared. At this, Lagertha retorted that Bjorn isn't Rollo's son, a denial which didn't sway Rollo from his conviction.

Per Hirst, Lagertha's denial doesn't refute Rollo's claim; it just shows that Lagertha genuinely isn't sure who Bjorn's father is and that she'd prefer to believe it is her ex-husband rather than her brother-in-law. "For me, I think there was a short period of time when she was sleeping with both the brothers and she doesn't really know who the father is," said Hirst.

Bjorn took a similar tack to Lagertha, telling Rollo that while it may be true that Rollo was sleeping with Lagertha at the time of his conception, so was Ragnar. Given that there are no DNA tests in this period, we'll likely never get confirmation either way, but Bjorn told Rollo that he won't acknowledge Rollo as his potential father because it is Ragnar whom he resembles most in appearance, in spirit and in principle.

Rollo continued to beg Bjorn to return with him to Frankia, promising him his every heart's desire. However, Rollo's decision to support Ivar was too painful for Bjorn to forgive, with Bjorn even attempting to kill Rollo in a heated exchange. But in the end, Bjorn spared Rollo's life, although he did get one seriously low blow in during the process. "You are not worth the time it takes to clean the blood off my hands," Bjorn said, walking away from a heartbroken Rollo.

At this, Lagertha formally refused Rollo's offer and the two shared a short farewell in which Rollo told the one true love of his life, "We will never meet again."

Could this line be true? Does this mean we've really gotten our last Rollo-Lagertha scene ever? It may be so. With the prophecy of death always hanging over Lagertha's head, we know her days are numbered. Meanwhile, Rollo is expected to live until a ripe old age. But just because Rollo may never see Lagertha again doesn't necessarily mean he won't return to the show in the future, sharing scenes with Bjorn. Or at least we hope so. If Rollo really is Bjorn's father, we'd hate to see things end between them like this.

Vikings airs Wednesdays at 9/8c on History.

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