I recently had a discussion with my uncle about Rome, and he brought up an interesting bit of history. He said that there is some evidence of a Roman Legion having been actively fighting for China. He said that they may have had such an impact on China that they actually had a city named after them.
Google has shown me that he isn't making this up, but I'm wondering what kind of hard evidence we might have. Did the Chinese or Romans ever write about these legionnaires? Is there any artwork that might be depicting them? Were the Chinese aware that these legionnaires were Roman? We're the Romans aware that their legionnaires were in China?
I can see a "Rome and China" section in the FAQ, but it wont open for me, so I'll ask anyway. Any good books you might recommend on this topic would be greatly appreciated!
The last time I looked at this, which admittedly was many years ago, we don't.
It's not impossible, but the entire theory rest on a passage in the Book of Han which, described some infantry fighting for the XiongNu in central Asia in fish-scale formation. And for some reason that is thought of as the legionnaires testudo, instead of what mostly likely was a generic shield wall. That is incredibly circumstantial.
According to the hypothesis, these men were captured and brought back to China. But even if they were Romans, in the passages afterwards the Chinese general gave the captives he took to 15 local central Asian kings, not take them back to China.
Recently DNA evidence show the people in Liqian in western China (which was supposedly derived from "legio", again, incredibly circumstantial) had Caucasian parts in their DNA, and it's pointed out that archaeology found people in the area had different culture and burial practices than Han Chinese in the river basins. However that's not weird at all. It's been known for a long time that central Asians had Caucasian ancestors, and there's no reason why these people weren't the descendants of Persians and related peoples instead of Europeans. Likewise just because their culture and burial practices were different from Han Chinese does not mean they were Romans. There's quite a lot of differing practices within China itself alone.
Someone provided a good answer to your question here: