The Qing dynasty did not allow civilians to go to the northeast. Why send prisoners?

Because the northeast is the birthplace of the Qing Dynasty (the emperor of the Qing Dynasty is Manchu), it is regarded as "the land of Longxing" by them. Therefore, people in Shanhaiguan are restricted from entering the northeast, which is sometimes prohibited. Until the end of the Qing Dynasty, due to the decline of national strength, Russia invaded the Northeast continuously. In order to resist the invasion of Russia, the Qing government began to emigrate to the northeast gradually, enriching the frontier and developing the local social economy. As for the prisoners being sent to the northeast, it is because of the natural environment in the northeast itself, high latitude, cold climate and low temperature, and the local social and economic backwardness, so the prisoners are exiled there, such as the famous Ningguta. Prisoners naturally suffer in the harsh wild environment.