[1] Under the reign of Emperor Gaozu, the king Suvarnapushpa (Chinese: 苏伐勃𫘝 Sufaboshi) provided the Tang court with tribute in 618.

[2] Kucha supported Karasahr when the oasis state made a marriage alliance with the Western Turks and ended its tributary relationship with the Tang court in 644.

Tang forces defeated the kingdom, captured the king, and a pro-Tang member of the royal family was enthroned as ruler.

The commander-in-chief of the Tang expeditionary army, Ashina She'er, was a member of the Eastern Turkic Khaganate ruling family.

[1] The Tang army bypassed Karasahr and struck at Kucha from the north by moving through the Dzungarian Basin, which was the territory of the Chuyue (possibly Chigil) and Chumi, two Turkic tribes allied with the oasis state.

The Tang army defeated the Chuyue and Chumi before entering the Tarim Basin, upon which the king of Karasahr fled his capital city and tried to find a defensible position in Kucha's eastern territories.

They chased after a group of 1,000 horsemen employed by Ashina as a decoy, but encountered additional Tang forces that mounted a surprise attack.

[9] In retribution for the death of Guo Xiaoke, Ashina She'er ordered the execution of eleven thousand Kuchean inhabitants by decapitation.

"[7] After Kucha's defeat, Ashina dispatched a small force of light cavalry led by the lieutenant Xue Wanbei to Khotan, ruled by the king Yuchi Fushexin.

All three men were given sinecures and kept at the imperial court until 650, when they were sent back to Kucha after it became clear that the vacuum of power created by their absence had reduced the kingdom to a state of civil war and anarchy.

[citation needed] It has long been claimed that the conquest of Kucha established Tang rule over the entire Tarim Basin.

[5] This is in part due to a number of inaccurate Chinese sources linking the expedition to the establishment of the Four Garrisons of Anxi, which comprised Kucha, Karasahr, Khotan, and Kashgar.

However, Zhang Guangda has used excavated texts from Gaochang (Karakhoja or Turfan) to show that the Tang abandoned the attempt to move the headquarters of the Protectorate of the Pacified West to Kucha after Guo Xiaoke's assassination.

Although the Tibetan empire collapsed in the middle of the ninth century, the Tang dynasty lacked the means to regain dominance in the Tarim Basin and itself ended in 907 with the abdication of Emperor Ai.