Irbis Bolun Cabgu

Irbis Bolun Cabgu (nickname: Sih Cabgu, also reported as Si Yabghu, personal name Irbis Ishbara) was a khagan (monarch) in the Western Turkic Khaganate between 631–633 or 630–632.

He was Tong Yabgu Khagan's son. His father was killed in 630 by Külüg Sibir a grand uncle. Külüg Sibir declared himself khagan, but could not maintain order. Especially the Nushibi tribes as well as Ni Shu a cousin of Irbis Bolun opposed him and supported Irbis Bolun to throne. Irbis Bolun however was not more successful than his predecessor. He couldn't control Syr-Tardush tribes and he executed so many people that even his former partisan Ni Shu planned to escape. That is why he was nicknamed Sih Cabgu (" unprincipled"). After losing his supporters and prestige Irbis Bolun escaped to south in 633. Ni Shu (with titular name Dulu Khan) succeeded him. Irbis Bolun tried to raid the city of Balkh (now in north Afghanistan), but was killed in the clash.

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