PUBLISHED: 16:32, Fri, Sep 11, 2020 | UPDATED: 16:32, Fri, Sep 11, 2020
Vikings airs on History and Prime Video, and the series was created by avid historian Michael Hirst. One of the characters in the series is Halfdan (played by Jasper Pääkkönen), and he is the brother of Harald Finehair (Peter Franzén). Halfdan made the decision to go travelling with Bjorn Ironside (Alexander Ludwig) rather than stay with his own brother, and fans are keen to find out why.
Halfdan was introduced in season four of Vikings and he is the brother of the Norwegian king, Harald Finehair.
Both brothers arrived in Kattegat so they could join Ragnar (Travis Fimmel) on raids in France.
Halfdan fought alongside his brother and even saved him from his former lover, Ellisif (Sophie Vavasseur).
However, at the end of season four he made the decision to explore the Mediterranean Sea in search for new settlements, which came as a surprise to his brother.
Bjorn ended up saving Halfdan's life on the trip, as they were about to both be executed. A sandstorm began and Bjorn used it as an opportunity to free themselves.
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Vikings: Halfdan chose to tour the Mediterranean with Bjorn (Image: Sky)
Vikings: Halfdan and Harald arrived in Kattegat together (Image: Sky)
Following their trip, Halfdan and Bjorn struck up a friendship which led him to choose Bjorn and his family over his brother in battle.
King Harald had joined Ivar the Boneless (Alex Høgh Andersen) in a bid to take over Kattegat, whereas Halfdan chose to fight for Bjorn and save his homeland.
Halfdan could not be persuaded by his brother to change allegiance ahead of the battle, so Harald took the opportunity to kill him in action.
Fans have wondered why Halfdan sided with Bjorn, and it could be to do with his difference in character compared to his brother.
Vikings: Halfdan and Bjorn went travelling (Image: Sky)
Harald was obsessed with status and leadership, whereas Halfdan was more interested in travelling and exploring new