I never thought Lagertha as weak but, she married such a jerk and stayed with him for so long. I wish the show had shown what his people did to make her Earl. Had they all felt sorry for her? Did they feel she was justified in stabbing him in the eye? She look so frightened when that guy whacked off her husband's head. They just didn't give us anything.
After returning to Denmark to fight a civil war, Ragnar divorced Lagertha to marry the daughter of King Herrauðr of Sweden. He sent to Norway for help, & Lagertha, who still loved him, came to his aid w/120 ships. Lagertha saved the day:"Lagertha, who had a matchless spirit...flew round to the rear of her enemy, taking them unawares, and thus turned the panic of her friends into the camp of the enemy." Upon returning to Norway, she quarreled w/her husband & slew him & usurped him.