Emperor Taizong's campaign against Xiyu statesとは 意味・読み方・使い方

Emperor Taizong of Tang (r. 626-649) of Tang Dynasty China, after subjugating the Eastern Turkic Khaganate, began to exert his military power toward the Western Regions, then dominated by the Western Turkic Khaganate as well as a number of city-states loosely allied with the Western Turkic Khaganate. In the year 640, Emperor Taizong sent the military commander Hou Junji to defeat and annex Gaochang -- the first attempt by any Chinese dynasty to set up permanent military and political presence in the region. In 644, after Yanqi -- an ally in the campaign against Gaochang—turned against Tang and allied with Western Turkic Khaganate, Tang's commandant at Gaochang, Guo Xiaoke (郭孝恪), attacked and captured Yanqi's king Long Tuqizhi (龍突騎支), but Yanqi subsequently broke away again. In 648, the ethnically Turkic Tang general Ashina She'er (阿史那社爾) who was second son of Shibi Khan, attacked both Yanqi and Qiuzi (龜茲, in modern Aksu, Xinjiang), conquering both. Both Shule and Yutian then also submitted to Tang, allowing the Tang Dynasty to dominate the region until it was briefly seized by Tufan (Tibet) during the reign of Emperor Taizong's son Emperor Gaozong.