Vikings: The many battles in 'On the Eve' 

‘ fourth season featured one battle that was expected and another that was inevitable. On a field in England, the sons of Ragnar met Aethelwulf’s army. In Kattegat, Lagertha struggled to defend her city against a violent coup. (Read the full recap here.) In our latest weekly postmortem, 

creator Michel Hirst talks about the Great Heathen Army – and what will happen to the sons of Ragnar Lothbrok after they achieve their vengeance.

ENTERTAINMENT WEEKLY: There were two major battles in this episode. Can you talk about what kind of preparation you do when you’re constructing the narrative of sequences like that? Do you read up on your military history? 

MICHAEL HIRST: I think we’ve made the point right from the beginning to do each battle differently. More than anything else, I hate those visual effects battles when you just get lots of identical warriors streaming from left to right and right to left.

I’m not a military historian as such, but I am interested in the history of warfare. When I was a young boy running home from school, I was always in Napoleon’s army, surrounded by thousands of soldiers. I can dive into historical books of any period and any culture. Some battles [on the show], to tell you the truth, were inspired by Japanese warfare. There’s a nod in the direction of Kurosawa’s film 

Ivar compensates for his lack of physical power with brain power. He is going to approach warfare in a different way. He’s appreciated that the scale has gone up now. The armies are bigger, the possibilities are bigger. We’re beginning to see something change in the show. You can expect [different] kinds of warfare, not just the shield wall.

I watched them shooting that big battle, and it was incredible. There were just hundreds and hundreds of warriors. People were 

themselves into the battle, horses running at each other.

Are you ever tempted in a scene like that to put on a helmet and go onscreen as an extra?

I’ll tell you a story. When we were doing 

, in the first season, one of the directors said, “Don’t you want a little cameo?” I said, “Okay, but I want to be the lowest of the low.” There’s a certain day when Catholics used to crawl to the cross. People in church, from the highest to the lowest, everyone would get on their knees, crawl to the cross, and kiss the cross. We were shooting the scene. I said, “I’ll be a peasant.” I did this with all the Irish extras and kissed the cross very devoutly. They were cleaning the cross between kisses, but obviously not enough because the next day my eye completely blew up. [

] I had to get on a plane to the States, so I had an eyepatch. I looked terrible. I was just being punished for my hubris! And, on top of it, they never used me in the scene!

The dynamic between Floki and Helge has been complicated all season since Helge brought the Spanish girl back from their raid. There’s a moment in this episode between the girl and Floki where he seems to be struggling to communicate with her. What is Floki feeling in that scene?

Floki never wanted Helge to take the child away from her culture. Floki still cannot come to terms with that act. By his own lights, he’s incredibly moral. He thinks it’s wrong. He feels for this girl, and it’s breaking the relationship with Helge. As he says, very honestly, “I don’t know what to do.” He has to hand her back to someone he knows she hates. One could sense an unhappy ending. There doesn’t seem to be any way of avoiding it. There’s a tragedy waiting to happen.

Ivar tells his brothers that he considers himself the true heir to Ragnar Lothbrok. The sons of Ragnar are all united now, but they are ambitious men in an ambitious society. Are Ivar’s brothers also considering this possibility, that one of them will be the standout inheritor of their father’s legacy? 

You can already sense the inherent tensions between them. They are only holding together because they have this joint cause. They are all committed to the act of revenge. Ivar

think he’s the true heir. Because it’s out there now, it promises that in the future, when the act of revenge is finished, the stresses and strengths are going to come more out in the open. This is a society fueled by the need for fame. We know they’re gonna be at each other’s throats.

After the battle of Kattegat, we saw that Torvi was lying dead amidst the mayhem. This has always been a high-fatality show, but what goes into the decision to kill off a long-running character like that?

You may be wrong! I do take your main point. A lot of thought does go into when a major character dies. It was funny, there was a character in earlier seasons, Torstein, who had his arm cut off. [The actor] was told twice that he was dead, and then I changed my mind and kept him alive. The producer whose job is it to tell character in advance that they are going to be killed is called the angel of death, even though he’s the nicest possible man he could meet. The angel of death twice went to tell him he was gonna die, and then twice, I went down later and said, “Actually, you’re not.” He kept looking around to see if I was coming!

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