In the Ming Dynasty, due to the Little Ice Age, natural disasters occurred frequently, and the outbreak of plague became the norm. There were about 330 plagues in the Ming Dynasty, which brought great challenges to the economy, people's livelihood and even politics at that time.
Due to the poor or no harvest in agriculture, people do not have enough to eat, and their resistance decreases, which increases the risk of catching plague. Drought is often accompanied by locust plague, with a huge number of locusts and amazing food intake, which creates favorable conditions for the reproduction, growth and survival of locusts.
Locusts eat the food that people depend on for survival, and then there is a phenomenon of "great hunger, following the epidemic, and people eat people" in the disaster area. Disasters such as drought, waterlogging and locusts fundamentally destroyed agricultural production, and the ensuing plague shook the survival of the victims, and the victims fled the disaster area and virtually expanded the scope of the epidemic area.
This large-scale plague can be said to have directly destroyed the defense lines inside and outside the Ming capital. On the one hand, at the end of the Ming Dynasty, the health system had completely collapsed, and the most elite army was Jiubian Town, and this plague directly destroyed Datong, Shanxi, Jizhou, Fu Xuan and other towns, resulting in a smooth road between Shaanxi and Beijing, and Li Zicheng was killed at the gates of Beijing almost effortlessly.
On the other hand, the 100,000 troops who stayed in the capital of the Ming Dynasty directly lost more than half of their lives in this plague. In the face of the invading army that had already killed the capital, the defenders even had to humble themselves and beg for help to defend the city, but they still "assembled in less than five or six days." Finally, even the eunuchs in the three or four thousand palaces went to the wall. Even so, there is only one soldier on the average of five battlements on the city wall, and the Ming army guarding the city in the plague is "like a pigeon, just a few words."
Faced with the panic of unknown dangers and the slow response of the government when the plague comes, people usually flee the disaster area with their families after the outbreak of the plague. This behavior directly led to the further expansion of the plague scale. In the seventh year of Chongzhen, a large-scale plague broke out in Taiyuan, Shanxi, and the people died at night. The family died overnight, leaving no legacy. People have fled and the city is empty. "
Plague is spread by insects such as fleas and blood-sucking animals. These people who fled in a hurry became the best hosts of the plague. As a result, the plague spread southward to Wu Yang County, Henan Province, resulting in "great plague, death of 19 people, and countless exterminations".