() The northern family of China, dominated by Confucian merchants, won the reputation of "a foreign trade family in Qing Dynasty". .

The Chang family in Yuci is famous for its foreign trade among Shanxi merchants. According to "Shanxi Foreign Trade News", "Among the many Shanxi firms engaged in trade with Russia in Chaktu, the one with the longest operation time and the largest historical scale is the first to promote the home of the Yuci car king. The school of Chang, from Qianlong, Jiaqing, Daoguang, Xianfeng, Tongzhi and Guangxu, went through seven generations, lasting 150 years. Especially in the late Qing Dynasty, among dozens of large firms in Chaktu, the Chang family occupied the fourth place, and was called a "foreign trade family" among Shanxi merchants in the Qing Dynasty. Chang Wei, the ancestor of Chang family business, went to Zhangjiakou to do business. When he left home, he was penniless, thinking that he was a fortune teller and earned money to eat and live. Chang Wei has three sons, the eldest son Chang Wanxi and the third son Chang Wanda, all of whom are good at doing business. Ten thousand branches, which was later called "south growth"; Wanda branch is "Beichang". Chang Wanda is a clever boy. When he grew up, he went to Zhangjiakou to do business with his father. He has been frugal for ten years, sincere and trustworthy, and has been highly praised by his colleagues in business. The Chang family made huge profits by opening cloth shops, selling cloth and white cloth, expanding its scale, engaging in tea and groceries, exporting to Mongolia and other places, gradually accumulating commercial capital and establishing Dadeyu Firm.

During the Qianlong period, Chaktu was designated by the Qing government as the only place for Sino-Russian trade. The huge trade transactions between China and Russia have been compressed to Chaktu. Chang Wanda saw the huge business opportunities. He renamed the "Dadeyu" run by Zhangjiakou as a teahouse, and poured his wealth into Chaktu, realizing the transformation from domestic trade to foreign trade. Changwangda exported tea to Russian businessmen, engaged in silks and satins, and imported fur and silver ingots from Russia, which made a lot of profits. Changwangda "is full but not profitable", constantly doubling its capital, laying a solid foundation for the development of Changjia's foreign trade. With the development of business and the increase of capital, Changshi has successively increased the names of Dashengyu, Daquanyu, Dameiyu and Dushenyu, forming the serial number of "Jade" of Changshi, which is spread all over Suzhou, Shanghai and Hankou. Du Shenyu also set up a branch in Moscow.

After the Gengzi Incident, Chang's business suffered some losses, and he turned to establish a modern family industry, and opened Dunyihe Sericulture Bureau and Dunmuhe Weaving Factory, which made a lot of profits. Chang also invested in modern industrial match bureau, mining company and Jinhua textile company. Chang, the 14th Chang, concurrently serves as the fourth general manager of the company. Often starting from business, the family is rich, and instead let their children learn Confucianism. Chang Ji, the eighth of the Chang family, was a county tribute student, the first in the family to pay tribute. Since then, there have been many successful students. By 192 1 year, four members of Chang's family went to Japan to study and returned to China, and 10 graduated from universities inside and outside the province, claiming to be "a scholar family", which is rare among Shanxi businessmen.

Chang's business gradually declined in the late Qing Dynasty and the early Republic of China, mainly because Russian businessmen owed huge sums of money and the Russian government imposed huge taxes, causing havoc. According to records, in Moscow alone, the cumulative compensation was 1.4 million yuan. After the Revolution of 1911, domestic and foreign loans were not settled, and the name of jade shops closed down.