This happened in Vinland Saga episode 19. After a duel between Thorfinn and Thorkell, Canute came and made some contract with Thorkell to join his side. Thorkell agreed with that, and out of nowhere, Askeladd laughs. What's the reason for Ashlad laugh at that time because there was nothing funny at that scene?
You could watch the episode on Youtube at 06:35
It's true that there was nothing humourous about the scene in the general sense, because in this scene Askeladd's laughing is the classic ironic laugh. It's that kind of laugh that an antagonist-type character usually makes, like when a small-fry character makes a brave stand and unexpectedly wins. He sees the irony in the fact that the crybaby weakling prince suddenly becomes the calculating cool calm character who got Thorkell to follow him and can't help but laugh, it's that kind of laugh.
