A Soviet-Norweigan co-production, most of the film was actually shot in Norwegians. The Danish characters speaks in their native tongue which is understandable to most Scandinavians. For the Soviet release, the Norwegian and Danish was dubbed over in Russian and lost some of the nuances of Old Norse culture. The Norwegian release, called "Dragens Fange" (Prisoner of the Dragon) simply subtitled the Russian.
The two main viking ships still exist, fully functional and are on exhibition in Vyborg, Russia.