First of all, the west mouth, now the specific meaning of the controversy, there is said to be the Yellow River crossing in the north of Shanxi to kill the tiger's mouth; there is said to be west of Zhangjiakou, Hebei. Anyway, in the Qing Dynasty generally refers to the north of Shanxi, Hebei Zhangjiakou west of the vast Inner Mongolia region, such as Baotou and other places. Because this is the border between the Qing government and the Mongols, so the land is sparse, further north is the Mongolian steppe, is the Mongols. During the Ming and Qing dynasties, passes were set up in the northern part of Hebei, Shanxi and Shaanxi, and the area north of the passes was called Beyond the Passes. Ming and Qing dynasties, and the Mongols for trade in goods, we must be in a few fixed points outside the mouth, similar to today's and Russia, Kazakhstan and set up a foreign trade ports in bordering places like. Shanxi merchants to go to the mouth to do business, they have to go out of the pass, and later called go west of the mouth. Later it became a generalized term, and merchants from Shanxi, Shaanxi, and Hebei who went to do business outside the port were called "Going West". Our ancestors are said to have gone to the west, that is, the Han people's cloth porcelain and other trafficking in the past, and then the Mongolian leather, horses back. In fact, this thing also has a great influence on the later generations, that is, a large number of Han people immigrated to the mouth, stabilized the border.
By the way, I would like to tell you about the recent big migrations that are equally famous as the "Going West" migrations, that is, the "Breaking into the East" and the "Going Down to the South" migrations.
Breaking into the Guandong, that is, the vast number of Han Chinese from Shandong and Hebei migrated to the Northeast north of Shanhaiguan, at that time, to open up land for farming.
Down to the South Seas, that is, the coastal people of Fujian and Guangdong, by boat to the islands of Southeast Asia.