Linked from
The 7 pages that link to Khanate of Sibir, each with the reason it gives.
Khanate of KazanRelated: It was another successor state in the political world around Kazan.
Yermak TimofeyevichNarrower topic: Yermak’s campaign targeted this state and its ruler, Khan Kuchum.
YasakRelated: Its defeat opened the way for Russian expansion and tribute demands farther east.
SurgutRelated: Its decline opened the way for Russian forts and settlements in the region.