Something I idly thought about. I know practical bullet proof vests are a relatively recent invention, at least in terms of something that you could issue to entire militaries, and even the ones soldiers use are limited in various ways, but if you had the resources, could you give a single soldier a bullet proof vest that would protect him from most infantry weapons of the war (so figure .30 calibre rifles of various flavors)? Ballistic nylon might not have been available back then (I dunno), but could they make ceramic or possibly concrete plates that would stop a bullet without stopping the soldier by being too heavy?
For purposes of bullet proof, let’s say the vest will stop at least a bullet. Repeated shots are a bonus, but let’s say stopping one bullet is still far better than what his old gear would have done.
I recall reading that the Archduke Franz Ferdinand wore a silk bulletproof vest (but the bullet slipped past an unarmored portion of him). Would such a vest have done anything against a rifle round if Franz were leading the troops on the battlefield?