Following the deadly third season, the History drama will introduce three new characters.

Following its deadly third season, History's Vikings is adding three new series regulars to its cast.

Finnish actors Peter Franzen (The Gunman) and Jasper Paakkonen (Frozen Land, Secret Lives) as well as Dianne Doan (Once Upon a Time) have joined the drama series created by Michael Hirst, The Hollywood Reporter has learned.

Franzen will play King Harald Finehair, a Scandinavian warrior and potential threat to Ragnar (Travis Fimmel). Paakkonen is set to play Halfdan the Black, Finehair's younger brother. Doan will portray Yidu, a new and unique Chinese character who will have a big role in season four.

Read more 'Vikings' Postmortem: Series Creator on Ragnar Twist and Season 4 Time Jump

Season four, already underway in Ireland, will feature a time jump of a "couple of years," Hirst told THR after the season three finale.

The castings come as Vikings said farewell to Jessalyn Gilsig's Siggy and George Blagden's Athelstan in its third season.

Franzen is repped by Paradigm and Untitled Entertainment, as well as Actors in Scandinavia; Paakkonen is with ICM Partners, Lisa Richards and Anonymous Content; and Doan is with Principals Talent Management.

Vikings returns in 2016.

Email: Lesley.Goldberg@THR.com

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