Kirata Kingdom (Kirat) in Sanskrit literature and Hindu mythology refers to any kingdom of the Kirata people, who were dwellers mostly in the Himalayas (mostly eastern Himalaya). They took part in the Kurukshetra War along with Parvatas (mountaineers) and other Himalayan tribes. They were widespread in the folds and valleys of Himalayas in Nepal and Bhutan.
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Kirata Kingdom Wikipedia(Text) CC BY-SA