Yabgu

Yabgu is a historical Turkic title used in early medieval Central Asia to denote a high-ranking noble who governed a provincial or regional wing of a larger khaganate. Often translated as viceroy, prince, or ruler of a sub-kingdom, the yabgu functioned as a key administrator and military commander within the empire while acknowledging the ultimate authority of the khagan.

In the major Turkic polities of the time, particularly the Göktürk (First Turkic Khaganate) and its successors, the realm was frequently divided into eastern and western wings. The yabgu typically presided over one wing, acting as a deputy or a semi-autonomous ruler who could mobilize forces, collect taxes, and administer civil governance in his domain. The exact degree of independence varied by era and circumstance, ranging from substantial autonomy to closer subordination to the khagan.

Over the centuries, as political structures evolved and new confederations emerged (such as the Uyghurs, Karluks, and others), the formal use of the title waned. In later scholarship the yabgu is primarily described as a historical office within early Turkic statecraft rather than as a surviving or ongoing title.

Sources from Chinese chronicles and Turkic inscriptions attest to the existence and role of yabqus, providing a picture of a layered imperial governance in which a leading noble could exercise real regional authority under the overarching authority of a supreme ruler. The concept of the yabgu thus contributes to understanding the organization of power in early Turkic and Central Asian polities.