Birger Schemes!

King Signy has been hard at work with his plan for vengeance, he was aware that Ragnar was no longer in Vestfold but he was also aware that the person in Vestfold right now was Lagertha.

Signy had a single objective and that was killing Lagerha so Ragnar would feel the pain he felt that day when he loses the person he loves the most in this world.

Birger was an indispensable warrior to Signy even though Signy didn't respect his uncle.

He had betrayed Asmund and sided with Xenophanes, this left his father in a weakened state.

If the King's brother could desert him without consequences, others wouldn't see this as a problem eventually but luckily for Asmund, he got the loyalty of his men because they wanted to be loyal and not because they were forced to.

Signy had captured Vingulamark and he was planning to launch an attack on Vestfold but he knew this would draw them into a battle with Ragnar's allies and this included Askild.