Güyük Khan, Mongol ruler, 3rd Great Khan of the Mongol Empire (born 1206)

Güyük Khan or Güyüg Khagan, mononymously Güyüg, was the third Khagan of the Mongol Empire, the eldest son of Ögedei Khan and a grandson of Genghis Khan. He reigned from 1246 to 1248. He started his military career by participating in the conquest of Eastern Xia in China and later in the invasion of Europe. When his father died, he was enthroned as Khagan in 1246. During his almost two year reign, he reversed some of his mother's unpopular edicts and ordered an empire-wide census; he also held some authority in Eastern Europe, appointing Andrey II as the grand prince of Vladimir and giving the princely title of Kiev to Alexander Nevsky.

Khagan or Qaghan is a title of imperial rank in Turkic, Mongolic, and some other languages, equal to the status of emperor and someone who rules a khaganate (empire). The female equivalent is Khatun.