Based on what I have read on various ancient armies, Roman, Mongol, Macedon, Arab, Gaulic, etc. Experienced soldiers seemed to be portrayed as more confident, brave, and bold with the more battles they fought.

I do admit I do not know nearly enough. My question is, was Posttraumatic stress disorder a big problem? Is there historical evidence that supports many veterans suffered from PTSD? How were those suffering from PTSD portrayed and treated? In modern times we know it to be a problem. If PTSD was not as prevelant in the past as it is in modern times, what might be the reasons?

EDIT: typo in the title, should be PTSD, not PSTD. Excuse my dyslexia, sorry.