I went to a civil war reenactment as a kid where there were food samples from the era available to try. Who knows how accurate they were, but given how passionate folks can be about that history I imagine a lot of work went into the food. I remember eating hardtack and a couple other things that, at least to my young palette, tasted ok. Of course the hardtack I tried surely had fewer weevils and maggots than most did during the actual war.