re: What would be the worst war to fight in in history?

Civil war for the confederacy toward the last months. Supplies were low and many marched barefoot with little food.

WW1 trench warfare
WW2 Eastern Front

All probably equally miserable but I think trench warfare is the worst.

Also revolutionary war in an open field British style battle where you line up 20 feet apart and mow each other down would suck. Minus a misfire it was pretty much a suicide.

Any type of dark ages war like the Crusades or the fight for Scottish independence. Charging each other with Spears and swords just sounds painful as hell

Civil War for sure, medical procedures, fighting family/countrymen, plus if you did survive, completely different country to go back home to.

In regards to more "modern" wars I would nominate the first world war for all of the reasons other users have listed already. People talk about various times in history being a hell on earth but I really think being on the western front in the first world war is the closest to hell mankind has come.

If we are talking about before the advent of gunpowder and modern warfare I would nominate the 2nd Punic War and specifically the Battle of Cannae. Hannibal surrounded an entire Roman Army and slowly over the course of the day cut their way inwards killing every single Roman soldier. The soldiers in the middle of the circle went mad with terror trying to bury their heads in the dirt or killing themselves rather than wait for the inevitable as they saw Hannibal close in. Of the estimated 86 thousand Roman troops 15000 escaped and thats because they were there in a support capacity.The death toll of the Battle of Cannae is compared to the first day of the Somme, it took over two thousand years for mankind to match the carnage from that one day.