Russian conquest of Siberia
The Russian conquest of Siberia took place between 1581 and 1778, when the Khanate of Sibir became a loose political structure of vassalages that were being undermined by the activities of Russian explorers. Although outnumbered, the Russians pressured the various family-based tribes into changing their loyalties and establishing distant forts from which they conducted raids.
Source: Wikipedia — Russian conquest of Siberia (CC BY-SA 4.0)