Did the Tang government restrict foreigners from entering China?

During this period, a large number of foreigners entered China, or did business, or bought land and houses for generations to settle down, and some even became officials in the Tang Dynasty. According to Mr. Xiang Da's "Chang 'an in Tang Dynasty and Western Civilization", in the early years of Emperor Taizong's Zhenguan (63 1), Turks "nearly 10,000 people went to Chang 'an, and their sincerity was amazing". In 787 AD, the Tang government inspected Hu Ketian's residence in Chang 'an, and there were 4,000 houses with land in Chang 'an. It is speculated that there should be more than 50,000 Hookers in Chang 'an, even more than100,000. The policy of the Tang government was very tolerant to so many foreigners. Emperor Taizong once said: "Since ancient times, China has always been the most important, and I love him as always. This thought has long guided the formulation of the foreign policy of the Tang government. Foreigners living in cities in the Tang Dynasty can maintain their religious beliefs, marriage customs, funeral etiquette and living habits, and can choose their own leaders. Immigrants from the same country can handle litigation cases according to their own laws and customs without discrimination. Even so, foreigners in the Tang Dynasty were not without any restrictions, and they had to abide by various laws promulgated by the Tang government. Especially in the aspect of intermarriage between foreigners and the people of the Tang Dynasty, the government of the Tang Dynasty imposed many restrictions. As early as the second year of Emperor Taizong's Zhenguan reign (628), the court stipulated that foreigners who marry Han women or Na Han women must stay in the territory of the Tang Dynasty, and foreigners are absolutely not allowed to bring Han women back to China. Moreover, as the famous sinologist Schaefer said: "For foreign residents, the best way is to choose the way of thinking and customs of the Tang Dynasty, and many foreign residents did the same at that time. "However, sometimes there are exceptions. According to Zi Tongzhi Bamboo Slips, during the Dali period in Tang Daizong, there were often thousands of Uighurs who stayed in the capital, and the number of mixed people was multiplied. "In view of this situation, the Tang government issued an imperial edict, stipulating that" those who are in the capital of Uighur Hu will take their clothes, which will have no influence on the Han people ",and it is strictly forbidden for Hu people to seduce Han women as wives or pretend to be Han people in any way. In the first year of Kaicheng in Tang Wenzong (836), lujun served as our envoy in Lingnan, forcing foreigners in Guangzhou to live separately from Han Chinese, forbidding them from marrying each other, and forbidding foreigners from occupying land and building houses. Later, China people and foreigners were further forbidden to "communicate, buy, sell, get married and associate" in private. Thus, although the Tang government adopted a relatively loose policy towards foreigners living in China, it was not without restrictions.