Shanxi merchants
At the beginning of Ming dynasty, the newly established government was in constant fighting with the remnant of the expelled Mongolian armies, along the northern border. In order to reduce the cost of logistics to transport food and other essential supplies to the military, the Ming government decided to grant salt sales license to those who deliver supplies for the frontier soldiers. The salt trade, as a high margin trade of essential goods, had been historically monopolized by the government to ensure enough tax, and the distribution of salt sales licenses served as one of the main profit sources for the early Shanxi merchants. Shanxi is located in North China close to the Ming-Northern Yuan border, and Yuncheng city in southern Shanxi has a very large natural salt production lake, therefore the geographical proximity was conveniently exploited by these merchants.