The oddest realization that I have for this sort of thing is just realizing how few people there were in those early years of history.
The best way that I can put it into words is the simple (if somewhat simplistic) observation that there are likely more people alive now who know how to forge bronze, or knap flint, or any of the other recreational re-creations of ancient crafts, than there were when those was the primary skillset, possibly cumulatively. There are probably more recreational horseback riders now then there were Mongol horsemen during the height of their empire, and that probably still holds if we toss in the European knights, too.
