In fact, the so-called shaving and braiding. It's not just the patent of Manchu people. In ancient times, northern nomads all over the world had such a similar tradition. As far as geographical influence is concerned. If you have experienced the cold current in Siberia, you may understand this. Humans originated in tropical and subtropical regions. From a biological point of view, human hair exists more for sun protection and heat insulation. It is not what we understand to keep warm. In cold areas, people mostly wrap their heads with hats and the like to keep warm. Running with a hat in winter will make you feel sweaty and warm. But once it stops, the sweat on the scalp will soon thaw. As a result, sweat and hair form ice residue and stick to fur. As long as you shave your hair, you can effectively solve this problem.
However, if these are just to satisfy the natural shaving. Then why did Manchu bother to leave a braid as a hairstyle? This is the hairstyle in the early Qing Dynasty. Braids are thinner than little fingers. In fact, this hairstyle is basically like a light perspective. So why can't Manchu people just shave their heads?
In fact, these things are more importantly influenced by the social level. In ancient times, wars between nomadic tribes in the north continued. Different braids become a symbol. Not only tribes can quickly distinguish between the enemy and ourselves on the battlefield. On the other hand, it also makes the tribe more United. This role is roughly the same as that of the current US Navy SEALs, and each team has similar tattoos, thus increasing the sense of collectivity.
Furthermore, as far as the rulers are concerned. The Qing Dynasty was a dynasty established as a foreigner. How to consolidate its rule is a serious problem. On the one hand, the policy of Manchu towards the Han nationality was to destroy the will of the Han nationality from the outside and fundamentally, so that the Han nationality was enslaved and gave up resistance. So as to accept the rule of the Qing dynasty. On the other hand, ethnic minorities' sense of self-satisfaction and honor as rulers.