Development Vikings is an Irish-Canadian co-production presented by
Metro-Goldwyn-Mayer. The fourth season was developed and produced by Octagon Films for the first sixteen episodes, TM Productions for the last four episodes, and Take 5 Productions. Morgan O'Sullivan, Sheila Hockin, Sherry Marsh, Alan Gasmer, James Flynn, John Weber, and
Michael Hirst are credited as
executive producers. This season was produced by Keith Thompson for the first eight and for the last four episodes, and Sanne Wohlenberg for the ninth to sixteenth episodes. Bill Goddard and Séamus McInerney are co-producers. The production team for this season includes casting directors Frank and Nuala Moiselle, costume designer Joan Bergin, visual effects supervisor Dominic Remane, stunt action designers Franklin Henson and Richard Ryan, composer
Trevor Morris, production designer Mark Geraghty, editors Aaron Marshall for the first, fourth, seventh, fifteenth and eighteenth episodes, Christopher Donaldson for the second, fifth and eighth episodes, Tad Seaborn for the third, sixth, ninth, eleventh, thirteenth, sixteenth and nineteenth episodes, and Don Cassidy for the tenth, twelfth, fourteenth, seventeenth and twentieth episodes, and cinematographers PJ Dillon for the first eight and last four episodes, and Owen McPolin for the ninth to sixteenth episodes. An additional original song not included in the album is "Snake Pit Poetry", written by Einar Selvik and performed by Hilda Örvarsdóttir, and featured in "All His Angels". Additional non-original music by Norwegian music group
Wardruna is featured in the episodes "In the Uncertain Hour Before the Morning" and "Crossings". The featured tracks are "Bjarkan", "Laukr" and "Algir — Tognatale". ==Reception==