This is not an unusual scene on Vikings. Blood is shed more often than not on the drama.
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King Horik makes a surprising proposition to Ragnar on the sixth episode of the second season of Vikings.
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Gaia Weiss Makes Her Vikings Debut on Season 2 Episode 6. It is titled "Unforgiven."
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Vikings Season 2 Episode 6 Quotes

I've chosen you to be the guardian of these books and their secrets. I want you to copy them.

King Ecbert

Bjorn: What if I ordered you to stay here?
Porunn: Then I would have to heed your command.
Bjorn: I don't want to order you. I want you to choose to stay here.