The fictional town of Smeerensburg was based on Smeerenburg, an actual town that existed in Norway. It used to be a prosperous whaling post during the 17th Century.
Director Sergio Pablos had wanted to do a traditionally animated feature film, but he wanted to see how the animation would have evolved without the switch to computer-generated animation. So the studio used CGI lighting techniques with hand-drawn animation to create a unique animation style for the story.
Neda Margrethe Labba, who voiced the Sami girl Márgu, did not speak any English. Sergio Pablos traveled all the way to Tromsø, Norway where she lives and did her whole recording session through translation and mimicry.
The film was shopped around to various studios, who perceived it as "too risky," from April 2015 until Netflix acquired the rights in November 2017.
It was originally planned for the Sami people to speak English but this was later changed and they spoke only their native language in the movie.