Vikings Episode 9 Recap: All Change (Season Finale)

This episode is aptly titled "All Change" since there are lots of changes afoot. No battles but major happenings occurred with all the characters. Here's the highlights:

Ragnar, Rollo, Loki and Bjorn are sent by King Horik to Gotaland (Jarl Borg territory). The King wants him to give back the land or else. Jarl tries to negotiate but no dice.
At the end of the episode, it looks like Rollo will unite with Jarl against Ragnar and the King. Its not going to end well for someone.
Ragnar's men spy on a woman bathing. She tells them Ragnar owes her an apology. He says he will apologize if she arrives "neither dressed nor undressed, neither hungry nor full, and neither alone nor with company". Turns out she is Princess Aslaug (daughter of Broomhilda). They flirt for two seconds and then have sex. Next she tells him she's pregnant. Uh that was really fast. Did Vikings have home pregnancy tests
Ragnar's son Bjorn is very upset that Ragnar is cheating on his mother. Can't say we didn't see this coming though. In the last episode Ragnar asked Odin "who will be the mother of my sons"? And the seer prophesied it as well.
Meanwhile back at home, the plague has arrived. Many people are dying. Siggy becomes sick and asks Lagertha to take care of her daughter. However a little later Thyri dies. Then Lagertha's own daughter Gyda dies. Poor Lagertha. She recently had a miscarriage, her husband is cheating on her, and her daughter dies. I said it at the beginning of the season but I'll say it again. Its not easy being a Viking.
Athelstan helps tend the sick but then became ill himself. Somehow he survives. I thought Siggy had died earlier but I guess she's still alive. I think both she and Rollo provide interesting conflict on the show so I hope she stays. Lagertha does not become ill as far as we know.
There is no mention of them trying to sacrifice Athelstan in last week's episode.
The plague (also know as the Black Death), killed 30-60% of Europe's total population during the Dark Ages. That is between 75 million and 200 million people total. It sounds like Siggy unknowingly brought it back to hervillage after journeying to a nearby one.