Did soldiers in large-scale melee battles get PTSD or similar mental disorders?

by nocbl2

Today we see many soldiers acquiring PTSD from fighting in wars, presumably because the advancement of modern transportation allowed them to see more combat than soldiers before them. However, the fighting soldiers saw back in, say, Roman times would have been visually a lot more brutal because it was so up close and personal. Did these soldiers come back shell-shocked from the death and destruction they witnessed right in front of them?

MI13

Not to discourage any other (informed) answers, but this is a pretty frequent question, so there's a number of threads in the FAQ on this subject already.