Yabghu (
Old Turkic: 𐰖𐰉𐰍𐰆, romanized: yabγu,[1]simplified Chinese: 叶护;
traditional Chinese: 葉護;
pinyin: Yèhù), also rendered as Jabgu, Djabgu or Yabgu, was a state office in the early
Turkic states, roughly equivalent to
viceroy. The title carried autonomy in different degrees, and its links with the central authority of
Khagan varied from economical and political subordination to superficial political deference. The title had also been borne by Turkic princes in the upper
Oxus region in post-
Hephthalite times.[2]
The position of Yabgu was traditionally given to the second highest member of a ruling clan (
Ashina), with the first member being the
Kagan himself. Frequently, Yabgu was a younger brother of the ruling
Kagan, or a representative of the next generation, called
Shad (blood prince).
Mahmud Kashgari defined the title Yabgu as "position two steps below Kagan", listing heir apparent Shad a step above Yabgu.[3]
As the Khaganate decentralized, the Yabgu gained more autonomous power within the
suzerainty, and historical records name a number of independent states with "Yabgu" being the title of the supreme ruler. One prominent example was the Oguz Yabgu state in Middle Asia, which was formed after the fragmentation of the
Second Türkic Kaganate in the 740s. Another prominent example was the
Karluk Yabghu, the head of the
Karluks which in the 766 occupied Suyab in the Jeti-su area, and eventually grew into a powerful
Karakhanid state.[4]
Etymology
There are at least several proposals regarding the origin of yabgu:
Yabghu might be a derivation from native Turkic root *yap- "to do, to carry out; to come nearer to help" and so might mean "the assistant (of the khagan)".[1]
Others suggest that the word is a derivation of the
early Turkicdavgu;[5] however, the d /ð/ to y /j/ sound change happened late (e.g. not before
Sui period (561 - 618 CE)).[6]
It is believed by some scholars to be of
Kushan (Chinese: Guishuang 貴霜) political tradition, borrowed by the
Göktürks from an
Indo-European language, and preserved by the
Hephtalites.[7] For example,
Harold Bailey reconstructs *yavuka ~ *yāvuka, which means "gatherer of troops" or "troop-leader" and is from base yau-, yū-, and yu- "to bring together", cognate with
Avestanyavayeiti, yūta and
Old Indianyú- "companion" and yūthá- "group";[8]
Others, such as Sims-Williams, considered that the word yabgu in
Turkic languages had been borrowed from
Old Chinesei̯əp-g’u > xīhóu,[9] rendered in
Chinese characters as 翕侯[10][11] or 翖侯[3] Conversely,
Friedrich Hirth suggested that yabgu was transcribed
literary Chinese, with regard to Kushan and Turkic contexts, as *xiap-g’u > xīhóu.[12] It was equivalent to the title yavugo found on Kushan coins from
Kabul, and the yabgu on ancient Turkic monuments. The second part of this compound Chinese word, hou ("g’u"), referred to the second-ranking of five hereditary noble ranks. Chinese sources do not make clear whether the title was a descriptive term used only in reference to foreign leaders, or whether it indicated an ally or subject of a Chinese empire;
Another theory postulates a
Sogdian origin for both titles, "Yabgu" and "Shad". The rulers of some Sogdian principalities are known to have title "
Ikhshid";[13]
^Hou Hanshu "Vol. 88: Greater Yuezhi nation"
text "初,月氏為匈奴所滅,遂遷於大夏,分其國為休密、雙靡、貴霜、駙頓、都密,凡五部翕侯。"
translation "Formerly, the Yuezhi were defeated by the Xiongnu. They then moved to Daxia (Bactria) and divided up this kingdom between five xihou (‘Allied Princes’), which were those of Xiumi (Western Wakhān and Zibak), Shuangmi (Shughnān), Guishuang (Badakhshān and the adjoining territories north of the Oxus), Xidun (the region of Balkh), and Dumi (the region of Termez)." by John E. Hill.