 In 766, after they overran the Turgesh in Zhetysu, the Karluk tribes formed a Khanate under the rule of a Yabgu, occupied Suyab and transferred their capital there.By that time the bulk of the tribe had left the Altai, and the supremacy in Zhetysu passed to the Karluks.Their ruler with the title Yabgu is often mentioned in the Orkhon inscriptions.