After he conquered the Qianzhong area (present-day eastern Guizhou Province), Tian Zongxian was recognized as the hereditary ruler of the region by the Sui court in 582.

[1] "Liangguang [ruled by] Cen and Huang, Sizhou and Bozhou [ruled by] Tian and Yang" (Chinese: 两广岑黄，思播田杨; pinyin: Liǎngguǎng Cén Huáng, Sī Bō Tián Yáng), an idiom current among Southwestern Mandarin speakers, proved that the Tian clan was once one of the most powerful clans in Southwestern China.

[3] The Chiefdom of Sizhou was established during the Sui dynasty when the first chieftain Tian Zongxian occupied Qianzhong area (黔中, modern-day eastern Guizhou) in southwest China.

Tian Mao'an (田茂安), the Sinan chieftain, swore allegiance to Ming Yuzhen, while Sizhou came under Zhu Yuanzhang's tusi system.

[6] In the same year, Guizhou Province was created,[7] both Sizhou and Sinan were fully annexed into the central bureaucratic system of the Ming dynasty.