From what I understand--which may be incorrect--Post-Tramautic Stress Disorder was not really understood or even addressed until Vietnam. This Wikipedia section mentions some reports during World War II, but did anyone receive treatment before then?
I specifically refer to WWI, but only because that war is especially interesting to me. Overall, anything regarding PTSD before WWII would be cool to learn about.
This book I read a while back called Achilles in Vietnam uses examples pulled from the Iliad to put some historical context into PTSD. Hope that is usefull, I am definitely not a historian though.
Shell shock in WWI was a major impetus for what we would now call psychiatric treatment protocols in Great Britain, including some early precursors to modern cognitive behavioral therapy (cf: William Rivers) as well as electroshock therapy (cf. Lewis Yealland).
I am sure there are earlier examples of PTSD itself (a quick search reveals this recent post on the Civil War), and would guess that the lack of a distinct psychiatric profession and perhaps a preference home treatment of "mental illness" would have meant that formal treatment would have been rare.