The answer: Because the Huns wanted genetic improvement.
The influence of culture
When I was in high school, my history teacher told us a very interesting story, but it was really sad.
The British minister reported to the Iron Lady that our television sets had been sold to the UK and had affected their sales.
Then the Iron Lady just asked faintly, did their TV show come to us?
And then the minister said, not yet, their show, not on our side yet.
The Iron Lady said, "Oh, then it's all right, sell the TV if you want."
The TV sold over, and there was no problem in stealing people's sales, but the only thing that the Iron Lady was afraid of was that our TV show sold over. Why? Because once we sell TV shows, it means that our culture has passed on.
The Huns' cultural inferiority complex
Maybe we don't have any good TV series, no good movies, no good anime, and no good cartoons. Of course, there was actually one more than ten years ago, such as the legend of the rainbow cat blue rabbit.
But in ancient times, our culture can almost be said to be the hottest fulcrum of the entire world culture, whether it is our Chinese medicine culture, whether it is our acupuncture, sauna culture or our papermaking, our various books are almost at the same time in the top of the leader.
At that time, although the Xiongnu burned and plundered us, it was because they had their own advantages, and the advantage was called war horses.
In the vast majority of cases, the reason why we Han Chinese can't defeat the Huns is because they fight on horseback, and they fight on horseback, but even so, the Xiongnu are very inferior.
This inferiority is not reflected in the use of force, after all, judging by the strength of the Huns, it seems that nothing is anything, and their greatest inferiority is the inferiority of culture.
The Huns didn't know when to farm, they didn't know when to wear clothes, they just lived by the weather, the festival, or the little bit of poor culture that their ancestors told themselves, but they found that we were different, we had sets of books, we had sets of wisdom systems.
Improving Genetics Program
What if a horse is of poor quality? If in the present we can of course use the method of genetic mutation or the method of genetic mutation to change the quality of this horse, but in ancient times we could only take the way of breeding.
In the same way, for the Xiongnu, the Han people can also use breeding to improve the quality of the Huns themselves.
We will find that the vast majority of Han Dynasty envoys could not come back at all once they arrived at the Xiongnu, and could only be forced to marry and have children. As for the great generals, once the marching army is captured, then don't think about coming back, and once you come back, you will inevitably come back with 7 or eight children.
There's another point beyond that
In addition to this, there is also a point, that is, the Xiongnu are actually a semi-slave society, but also a semi-matriarchal society. The Huns mostly had a natural dependence on the population.
Since they were somewhat dependent on population, they had to have a large population, and the Xiongnu, without a large population, could only force some Han Chinese to have children by capturing them.
Of course, this factor may not be very important, but the most important point is the sense of cultural inferiority.
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