The Oirats are a major western branch of the Mongol people, dating from at least the time of Chinggis Khan (1162–1227 CE). The Oirats have several historically important sub-branches. The leader of Khoshud branch, Güüshi Khan (1582–1655), allied with Gelukpa monasteries and occupied Tibet in the 1630s–40s, and was named king. Together, they established the Ganden Podrang government in Lhasa with Dalai Lamas at its head. The Zunghar branch established a state in eastern Central Asia in the early seventeenth century, and played a significant role in the political and religious affairs of the eastern Khalkha Mongols, as well as Tibet in 1717–20. The Kalmyk branch, which migrated to what is now southwestern Russia in 1607–30, are the only majority-Buddhist ethnic group on the European continent.