There have been enough battles, power struggles, tears and bloodshed to fill four seasons of the hit TV show Vikings but there's plenty more where that came from with season 5 on its way. 

There was plenty teased in the promo, which points to quite a few corners being turned in the plot, although no calmer waters for the Vikings in sight just  yet. 

Last season saw King Aelle and King Ecbert killed off by Ragnar's sons in an act of vengeance.  But a new threat to the Vikings is in town with Heahmund, played by Jonathan Rhys Meyers.

He first landed on the scene in the finale episode of season 4 and he is here to stay, as he's gunning for the Vikings and particularly, it is reported, Ivar.

Ivar, fans will recall, killed Sigurd last season. 

Sigurd's burial will kick things off in episode 1 and it will be an emotional event, as the season 5 promo teases Ivar crying at his brother's funeral. 

Rollo and Floki are all set to return to the show following the death of Ragnar, and for Floki it will be a time of inner struggle. 

Showrunner Michael Hirst teased to Variety that Floki is a "destroyed" man following the deaths of his daughter, Ragnarand Helga.  His conclusion is to turn himself over to the gods. 

"Floki is going to commit himself to the gods. His previous life is over — he might as well be dead. The new season will find him submitting to the will of the gods," Hirst told Variety.

With Floki's attention on his spiritual struggles and Bjorn away on his Mediterranean mission, Hirst teased a possible power struggle between Ivar, Hvitserk and Ubbe.

"They split up into different camps," he told Variety.

He added that there was enough material for at least another two seasons of the hit History channel show, although the air date for season 5 still has not been confirmed.