The Tartars.

The Tartars and the Vikings maintain a fragile peace in the harsh landscape of the Russian Steppe. When the leader of the Vikings, Oleg, declines to accompany the Tartars on a campaign against the Slavs, there is an explosion of violence. After Oleg kills the Tartar leader and kidnaps his daughter, the dead man's brother, Burandai, retaliates by holding Oleg's wife, Helga, hostage. The stalemate can be resolved only on the battlefield.