Vinland Saga Season 1 Episode 10

Askeladd's army separates from the army of Denmark and attacks a village 100 km to the west. Thorfinn leaves the soldiers behind in disgust and climbs up a hill overlooking the village, where he pledges revenge for his father. However, he encounters Askeladd sitting in the darkness, who tells him about "Britannia", the aging of the world, and Ragnarok, the final battle.