Protectorate of the Western Regions

The Protectorate of the Western Regions (simplified Chinese: 西域都护府; traditional Chinese: 西域都護府; pinyin: Xīyù Dūhù Fǔ; Wade–Giles: Hsi1-yü4 Tu1-hu4 Fu3) was an imperial administration (a protectorate) situated in the Western Regions administered by Han dynasty China and its successors on and off from 59 or 60 BCE until the end of the Sixteen Kingdoms period in 439 AD. The "Western Regions" refers to areas west of Yumen Pass, especially the Tarim Basin in southern Xinjiang. These areas would later be termed Altishahr (southern Xinjiang, excluding Dzungaria) by Turkic-speaking peoples.

Source: Wikipedia — Protectorate of the Western Regions (CC BY-SA 4.0)