Lets see how many we can find here. These will be actors who in real military service was in a battle or in circumstances and years later would see them now as actors in the same same battle or n the same circumstances.
Here's one I found only recently, and was totally unaware of.
Percy Herbert right, he was in a lot of stuff., like The Cockleshell Heroes etc etc. I remember him best as Mister Riddick, Battalion Sergent Major in Tunes of Glory , a heavy, excellent soldier no doubt, but a heavy.
I also know he was in Bridge on The River Kwai, but what I didn't know is that he was a member of the Army, the Royal Army Ordnance Corps, probably a pre war guy. In 1941, he posted at Singapore, and goes into the bag when the Japanese win.
Although he wasn't sent to Thailand, he stays in Singapore at the notorious Selarang Barracks/Changi.
In fact Herbert was a consultant in the very movie he acted in.