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 imposed by Han China – between the 2nd century BCE and 8th century CE – on many smaller and previously independent states, which were known in China as the "Western Regions" Chinese: 西域; pinyin: Xīyù; Wade–Giles: Hsi¹-yü⁴).

"Western Regions" referred mostly to areas west of Yumen Pass, especially the Tarim Basin. These areas were later regarded as Altishahr (southern Xinjiang, excluding Dzungaria). Previously, "western regions" was used more generally in regard to Central Asia and sometimes even included parts of South Asia.

The protectorate was the first direct rule by a Chinese government of the area. It comprised various vassal protectorates, under the nominal authority of a Chief Protector of the Western Regions, appointed by the Han court.

In the Han–Xiongnu War of the 2nd Century BCE the Chinese state established a military seat at Wulei (near present-day Cedaya 策达雅, in Bugur/Luntei County). Their aim was to control the diverse peoples and cultures of the Western Regions at the time, including several originating in Western Eurasia and/or spoke Indo-European languages. These peoples included the -speaking city states, such as Ārśi (Arshi; later Agni/Karasahr), Kuča (Kucha), Gumo (later Aksu), Turfan (Turpan), Loulan (Krorän/Korla). By controlling the Western Regions, the Chinese would also keep the Xiongnu away from Inner China. The peoples of oasis city-states of Khotan and Kashgar spoke the Saka language, one of the Eastern Iranian languages.

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