Vikings: Valhalla” showrunner and creator Jeb Stuart has fathered four kids, and he’s about to pop out his fifth — in the form of the Netflix sequel series.

“I’m ready to have this baby,” Stuart says. “There’s so much anticipation, especially when you’ve come to really love a project, and love the group of people you work with and they all care about it and have put so much into it. I’m so excited.”

Stuart, whose filmography as a screenwriter includes “Die Hard” and “The Fugitive,” wound up developing the highly anticipated streaming sequel to Michael Hirst’s celebrated historical drama “Vikings” — which takes place a century after its predecessor, and packs in more action and adventure without sparing accuracy — because of another show he made for Netflix.

“I was developing a show called ‘The Liberator,’ and Morgan O’Sullivan, one of the executive producers for ‘Vikings,’ had been slated to produce,” he says. “I wound up getting to know him well. During that time, we were going to shoot it over in Europe, and I would come and go through Ireland for a meeting or two, and would often pop down to the ‘Vikings’ set and that’s how I got to meet Michael.”

After they wrapped Season 6, Stuart was approached by O’Sullivan who had said that there was a possibility that “Vikings” wouldn’t mark the end of the franchise. Stuart was hesitant, and spoke with Hirst about how he had no desire to do a Season 7, but that he was open to the possibility of creating something new with the DNA of the old. Stuart noted how inspired he has been by the way the “Star Trek” franchise has expanded on TV and in film, and how he longed to accomplish something similar for “Vikings.”

After conducting hours of research, Stuart wound up settling on a time period about 125 years, give or take, beyond when Hirst’s “Vikings” ended. (“Vikings” begins with the Lindisfarne raid in 793, widely considered to be the start of the Viking Age.) He felt comfortable in that period, tackling the problems the Vikings were dealing with, what they were doing, and where and how they were marking their legacy in history.

Stuart dove into the process of creating “Vikings: Valhalla” for Variety, including ensuring accuracy in action-sequencing and prayer-saying, as well as goals for building an audience for the Netflix sequel of the original show.

You aren’t just the showrunner and the executive producer of “Vikings: Valhalla,” but you also wrote several of the first season’s episodes. What research did you have to put into all of this, and what were some of the most interesting historical insights you gleaned from the process?

You can’t follow a show — much less write a show — like “Vikings” and just sort of wing it. You have to depend upon really good teachers that you bring in to tell you what you can and can’t say and do. I knew a good bit about the Vikings already, but I read everything I could possibly get my hands on — especially about the latter part of the Vikings era. It was integral to understand where the Vikings came from, but that was Michael’s show. What I wanted to do was pick up in the sort of second half of the Vikings era, so I really dug into that. I also read a lot of esoteric stuff that’s out there, coming from modern research at archaeological digs and things like that. I wanted to feel like an expert, and I don’t use that term lightly. Even when we bring new writers into the room and onto the team, they must go through a very extensive reading and research period.

What was going through your head when it came down to making casting decisions?

I’m deeply entrenched in every aspect of this show, including casting. We have a fabulous crew in Ireland and a fabulous casting director, Frank Moiselle, who had done the casting for the original series. I leaned a lot on Frank. We primarily cast out of Europe and internationally, as opposed to casting out of the “New World” of Hollywood, USA. We also knew we had to get a different type of cast from the original because the show is much more active, so I wanted to have my cast have a lot of those sensibilities. Also, my “Vikings” prototype is split amongst three different main characters, rather than Michael’s show which wove the thread through one character, Ragnar Lothbrok.

There are a bunch of scenes where characters pray or recite a couple of lines in Old Norse. How did you find a way to incorporate those moments seamlessly in the script?

I practically sleep and dream in Old Norse nowadays. A lot of that would come up in the research; we would come across a beautiful prayer, captured in some writing or maybe on a rune stone, that was in Old Norse. They are tied to the incoming tide of Christianity, and the outgoing tide of the more pagan, traditional Viking faith. We wanted to invest something in both of those cultures due to the era, and it was interesting as a writer to find ways in which to combine them. We remembered pieces that we had come across in our research and tried to incorporate them as much as possible.

Your start as a writer was rooted in action flicks, and there’s a lot of that influence evident in this show. Would you mind going into that more? Does producing a show for a streamer give you more leeway in what adventure or violence sequences you’re able to depict on-screen?

I did start in this business with “Die Hard,” and I love action. It is a genre that I feel is near and dear to my heart, as someone who has put in well beyond the requisite 10,000 hours to get a hang of the genre. The type of action most evident in “Vikings: Valhalla” is character-based action— an action that lends to the plot and has to do with the character that the actors are playing. I did not want to have my Greenlanders know how to fight the same way as other Vikings who had grown up with raids like the Norse or the Swedes. The Greenlanders are very physical, but they are hunters.

So, how do you dramatize that? That’s what I mean by character-based action. We spent a lot of time with one of the greatest stunt coordinating teams in the business, led by Richard Ryan, and his team is expert in fine-tuning and accuracy and figuring out what we want to do with the world we are building from our scripts. I’ve worked with some great stunt coordinators and some not-so-great stunt coordinators, and every now and then, you turn in a script that you think you’ve really nailed, and then when you see the finished product and choreograph, you’re like, “Wait a minute, didn’t you guys read the script? This is nothing at all like that.” We are accomplishing what we need to in order to tell the story. I am working with a crew that is understanding, fun and strong.

There are so many extras involved in this series and the cast is enormous — not just the ensemble, but overall. What was it like to film with so many people during the pandemic, and how did you all ensure things went as smoothly as possible?

The hairs actually rose on my back remembering this exact issue. It is a tremendous challenge to shoot a big action show in the teeth of COVID. First of all, we have some of the best extras that I’ve ever worked with— they are passionate, they know what we’re trying to accomplish, and they work with the cast and crew so well. They bring their own knowledge and passion. That said, we’re doing a show that requires things to be planned down to the nth degree, and we also have to dress them and put them through makeup, and then we have to test them for COVID and you’ve got to get them out there and, finally, have a limited day to do this all.

I don’t think we could have done it without the talents of the tremendous crew in Ireland. We tested people two or three times a week, on average. We had to work with the government in terms of how many people we could put out there and the limits of who could have masks on, who couldn’t have masks on. It’s one thing to have 30 or 40 people take their masks off for some scenes, it is another entirely to have over 200 people in masks take their masks off for some scenes, act, and then go back to their first position. Like a lot of showrunners, I am praying for better days ahead. But, I’m really pleased with the scenes we got. We got some epic, big fights.

How are you hoping to hook-in audiences to the “Vikings” universe that may not have seen the original “Vikings” on the History channel?

It’s always tricky following a successful show with a following. One thing that I do know was going to be a recipe for failure was trying to do a show that was “Jeb Stuart writing a Michael Hirst script.” We’re just two entirely different writers. That said, I am a huge fan of the original show, so I’m actually trying to please fans like me, and at the same time, trying to make a show that would reach a bigger audience in some respects so it doesn’t have to seem too much like “Vikings.”

“Vikings” was written with a different framework. What you can do on a Netflix show you can’t do, say, on a network show. I can kind of make a mini-movie every week. My tastes lean into action, lean into suspense and lots of character-building. At the same time, we’re actually shooting on some of the same sets and some of the same locations. We only use one actor from the original series, who is sort of transcendental, but there’s a lot of new freshness to it overall.

“Vikings: Valhalla” stars Sam Corlett, Frida Gustavsson, Leo Suter, Bradley Freegard, Jóhannes Haukur Jóhannesson and Caroline Henderson. All eight episodes of the inaugural season air on Feb. 25 on Netflix. 

This interview has been edited and condensed.