King Ragnar Lothbrok's son Bjorn Ironside is likely to marry Princess Gisla towards the end of 'Vikings' season 3.Facebook/Vikings

History Channel has renewed "Vikings" for season 4 and it will reportedly revolve around King Ragnar Lothbrok's (Travis Fimmel) son Bjorn (Alexander Ludwig).

While informing media about the renewal of drama series, Dirk Hoogstra, executive vice president and general manager of History and H2 at A&E Television Networks, revealed that the cable network is proud of the team. 

"We are so proud of our immensely talented cast and crew led by Michael Hirst, whose intriguing story-lines and pivotal arcs have the perfect balance of scope, smarts and bloodshed to keep our loyal fans watching and wanting more," Variety quoted him as saying. 

Meanwhile, Hoogstra also stated that the series has not only won the hearts of viewers but also the critics. "Vikings has raided the hearts of both audiences and critics, establishing itself as one of the most compelling, visually stunning dramas on television."

The show is rated as one of the top rankings of Thursday nights with an average of 4.3 million total viewers, among which two million belongs to 18-49 category and 2.2 million are of 25-54 group.

The filming of season 4 will reportedly begin by end of March or the beginning of April and will take place in Ireland, according to Deadline.

In the meantime, creator Michael Hirst revealed that he has already completed scripting five episodes of the upcoming sequel. "I've written five episodes [of season four]. We're going to do more episodes this year, I think we're doing 16. I have a huge hope that we can continue [beyond that]," he told Radio Times.

He also teased that "Vikings" season 4 will revolve around Bjorn. "I always anticipated continuing with Ragnar's sons because many of them became as famous, if not more famous, than he was," he said.

"There was the rather remarkably named Ivar the Boneless and Ragnar's elder son [Bjorn] who sailed around the Mediterranean, and then they went to Iceland and Greenland. So much happened in the early years of the Vikings it's incredible, which is why I wanted to start at what was essentially regarded as the beginning of the Viking age," added Hirst.