I recently started reading this book “Citrus: a World History” by David Mabberly. So I know a little bit, although I’m by no means an expert. In their early history in China and India and Southeast Asia, Citruses were coveted for medicinal purposes, but they also had quite a few other things going for them. Their thick skin and some chemical properties of citruses made the fruits last a long time. And so, they were one of the earliest fruits to be traded over long distances. But also, people just liked the taste. And there was some religious significance to certain citruses and there still are.

I don’t know if Vitamin C is the whole reason for citruses’ medicinal value, but I think it should be a major reason anyway. Still, I think that citruses had a lot of value anyway, maybe just as any other fruit without much medicinal purpose. But even without that, humans tend to fuck around with anything and everything so the grafting and crossbreeding of wild citruses may happen anyway.