...Do you study ancient warfare as well as medieval warfare?

Yes, I've always been interested in ancient history. I draw on as many sources as I can.

Your homepage states that you "directed chess tournaments for the Continental Chess Association 1973-1976". I used to be an avid chess player myself (now I mostly play coffee-chess), and I wondered if you still play chess?

Not for many years, I'm afraid. I was a very active player in the 60s and 70s, and at one point had an expert's rating, but that was a long time ago...