The ancestors of the Kaifeng Jews in China arrived there no later than the early Middle Ages, and Jews were in China during the Han Dynasty, i.e., during the Roman Empire. Rome and the Han Chinese conducted commerce by sea and overland; the silk route is so old that it’s not too much to speculate that members of the Israelite tribes (including the “lost tribes”) entered China during the eventful centuries of the post-Judges kingdoms.
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