Ragnar may be faced with a new foe abroad, but the Vikings homeland will also be seeing a bit of upheaval as the series moves into "Trechery."

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A new raid on Wessex is in full swing with Ragnar (Travis Fimmel) and King Horik (Donal Logue) at the helm, but the Norsemen may have bitten off more than they can chew when the chose to engage the very ambitious King Ecbert (Linus Roache). Meanwhile, back in Kattegat, Jarl Borg (Thorbjørn Harr) is getting a little power made as Aslaug (Alyssa Sutherland) gives birth to her second child with the absent Ragnar.

As Ragnar move to dominate Wessex, he will soon learn that Ecbert is not easily swayed.

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"He's driven by ambition but I think he's is also driven by vision, which is basically to become like a mini emperor of all the kingdoms of England," Roache explained in a History channel featurette. "I think Ragnar has definitely met his match in Ecbert because like Ragnar, Ecbert isn't tied to tradition - he's a radical thinker. So that makes him a formidable foe."

Aslaug is also highly ambitious, and she will giver her new child a formidable family name. Taking into account her young son's strange eye ailment, Aslaug will call him Sigurd Snake-In-The-Eye in honor of her father.

Vikings airs Thursdays at 10 p.m. ET on History. Click the video below to view a preview of "Treachery."