Khaqan

Kha Khan or Khagan or Qagan (Mongolian: хаан, Khaan; Mongolian Script: ᠬᠠᠭᠠᠨ, Qaγan; ) is a title of imperial rank in the Mongolian language equal to the status of emperor and someone who rules a khaganate (empire). The female equivalent is Khatun.

It may also be translated as Khan of Khans, equivalent to King of Kings. In modern Turkic, the title became Khaan with the 'g' sound becoming almost silent or non-existent (i.e. a very light voiceless velar fricative); the ğ in modern Turkish Kağan is also silent. Since the division of the Mongol Empire, emperors of the Yuan dynasty held the title of Khagan and their successors in Mongolia continued to have the title. Kağan and Kaan are common Turkish names in Turkey.

The common western rendering as Great Khan (or Grand Khan), notably in the case of the Mongol Empire, is translation of Yekhe Khagan (Great Emperor or Их Хаан).

The title was first seen in a speech between 283 and 289, when the Xianbei chief Tuyuhun tried to escape from his younger stepbrother Murong Hui, and began his route from the Liaodong Peninsula to the areas of Ordos Desert. In the speech one of the Murong's general named Yinalou addressed him as kehan (Chinese: 可寒, later Chinese: 可汗), some sources suggests that Tuyuhun might also have used the title after settling at Qinghai Lake in the 3rd century.

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Wikipedia