Emperor Wen of Sui Emperor Yang Jian changed the three-level administrative divisions of state, county, and county in previous dynasties to the second-level state and county; His son, Emperor Yang Guang of the Sui Ming Dynasty, changed it to the second level of county and county, and its essence was the same, except that the "state" was changed to "county". Pen | fun | pavilion www. ｂｉｑｕｇｅ。 infoTang Dynasty followed the Sui Dynasty's second-level administrative division mechanism, and initially set up prefectures and counties; By the time of Emperor Xuanzong of the Tang Dynasty, the "state" was changed to "county", which was the second level of county and county, and a "house" was set up in places that were considered important.

The Tang Dynasty also set up "roads" in the prefectures, but did not have fixed governors, but because of the need for the central government to temporarily appoint the responsible persons of the provinces, to inspect and inspect the prefectures and counties under their jurisdiction, and only played the role of supervision and inspection.

In 640 (the fourteenth year of Zhenguan), according to statistics, there were 360 prefectures (prefectures) in the Tang Dynasty, with 1,557 counties under its jurisdiction.

As early as 627 (the first year of Zhenguan), the imperial court divided the country into ten "roads" according to the direction of mountains and rivers and the characteristics of landforms: Guannei Road, Henan Road, Hedong Road, Hebei Road, Longyou Road, Shannan Road, Jiangnan Road, Huainan Road, Jiannan Road and Lingnan Road.

The jurisdictions of each province are roughly as follows:

Guannei Road: It is equivalent to the central and northern parts of present-day Shaanxi, Longdong of Gansu and Hetao of Inner Mongolia.

Henan Province: It is equivalent to the area south of the Yellow River in present-day Henan and Shandong provinces, and north of Jiangsu and Anhui provinces.

Hedong Road: It is equivalent to the area of present-day Shanxi Province and the northwest part of Hebei.

Hebei Province: The area north of the Yellow River and south of the Great Wall of Hebei Province, which is equivalent to the two provinces of Henan and Shandong.

Longyou Road: It is equivalent to Longxi in present-day Gansu, east of Qinghai Lake in Qinghai Province and eastern Xinjiang.

Shannan Road: It corresponds to the eastern part of present-day Sichuan, the southwestern part of Henan, the western part of Hubei, Shaanxi Province and the southern part of Gansu.

Jiangnan Province: It is equivalent to the four provinces of Jiangxi, Zhejiang, Fujian and Hunan, south of the Yangtze River in Jiangsu and Anhui, Jiangnan in Hubei and Sichuan, and northeast Guizhou.

Huainan Road: It is equivalent to the area south of the Huai River in present-day Jiangsu and Anhui provinces, and the area north of the Yangtze River in eastern Hubei.

Jiannan Road: It corresponds to the area of present-day central Sichuan and northern Yunnan.

Lingnan Road: It corresponds to the two provinces of present-day Guangdong, Guangxi and northern Vietnam.

In addition to these states and provinces in China, the Tang Dynasty and the Wu and Zhou dynasties also set up the capital protectorate (later also known as the Dadu Protectorate) in the border areas. After Tang Taizong pacified Gaochang, he began to set up the Anxi Protectorate; Later, during the period of Wu Zetian and Gaozong's joint government and Wu Zetian's sole rule, it was gradually increased, and by the time of Wu Zetian's Wu Zhou Dynasty, with the continuous expansion of the territory, there were nine capital protectorates, including Andong, Dongyi, Anbei, Shan Yu, Anxi, Beiting, Kunling, Mengchi, and Annan, and the jurisdiction of Tang Taizong's Anxi capital was expanded geometrically; But by the time of the ruined son Tang Xuanzong Kaiyuan Tianbao, there were only 6 capital protectorates left: Anxi Metropolitan Protectorate, Shan Yu Metropolitan Protectorate, Anbei Metropolitan Protectorate, Andong Metropolitan Protectorate, Annan Metropolitan Protectorate, and Beiting Metropolitan Protectorate.

The capital of the Tang Dynasty was divided into three types: the Great Metropolitan Protectorate, the Upper Metropolitan Protectorate, and the Lower Metropolitan Protectorate.

Anxi Protectorate: The largest jurisdiction once included the north and south of the Tianshan Mountains, and the west reached Persia (now Iraq)! It is all of present-day Xinjiang and Kyrgyzstan, most of Afghanistan and Uzbekistan, eastern Tajikistan, northeastern Iran, eastern half of Turkmenistan, eastern and southeastern Kazakhstan. After the establishment of the Beiting Protectorate in the Wu Zhou Dynasty, the Anxi Metropolitan Protectorate was in charge of the Western Regions south of the Tianshan Mountains. It covers 16 states west of Khotan and east of Persia, and governs 16 prefectures, 80 prefectures, 110 counties, and 126 military prefectures.

The prefecture was successively set up in Xizhou (in present-day Xinjiang) and Qiuci (in present-day Kuqa, Xinjiang).