Yiran Khan

When Bilge Khan died of poison, “the people set up his son as the Yiran Khan”.^[1] The Tang sent Li Quan to offer the condolence sacrifice, to invest Yiran, and to build a stele and a shrine. The court historian Li Rong composed the text. Then, in the words of the Tang history, “before long Yiran died of illness, and his younger brother was set up as the Tengri Khan”.^[1] That is the whole of what is known of him.^[1] The Bilge Khan inscription is spoken by a son of the dead khan, who held the funeral in the fifth month of 735. Whether that son was Yiran or already Tengri depends on how long Yiran lived. No source says how long that was. Modern accounts give him the single year 734.^[2]

Accession

The reign begins with a poisoning that the poisoner did not survive. Bilge Khan was poisoned by his own great officer Meilu Chuo. The drug took effect, but he did not die at once. Before he died he had Meilu Chuo hunted down and executed, and he had his whole faction destroyed.^[1] Only then, with the killer already dead, did the people set up his son.^[1]

The Tang response

Chang’an treated the succession as an occasion of state. Li Quan, head of the Court of the Imperial Clan, was sent to offer the condolence sacrifice and to invest Yiran. A stele and a shrine were built for the dead khan. The court diarist Li Rong was ordered to compose the inscription.^[1] The same honours had been given two years earlier for Kül Tegin. The emperor had written that text himself.^[1]

Then comes one clause: before long Yiran died of illness, and his younger brother was set up as Tengri Khan.^[1]

The one later trace

Yiran reappears once, eight years after his death and only through his household. The khaganate collapsed in 742, and the refugees came south. The list of those who surrendered includes the junior wife of Yiran Khan, named Yusaifu. It also names the wife and children of the Western Shad, a grandson of Kapgan, a daughter of Bilge Khan and a daughter of Tengri Khan.^[1] They were brought to Chang’an in the eighth month of 742. They were presented first at the imperial ancestral temple and then in the palace courtyard. The emperor wrote a poem about it.^[1]

That list is the last appearance of the house of Bilge in the Chinese record. Yiran’s widow is in it.