The women who fought as men: Rare American Civil War pictures show how females disguised themselves so they could go into battle
To his comrades in the Union cavalry, Jack Williams was definitely one of the boys - a hard-drinking, tobacco-chewing, foul-mouthed son of a gun.
Outstanding on horseback, he was as deadly with a sword as he was around the poker table - just the sort of fella you would want by your side when the going got rough.
And for Jack it frequently did. By the end of a distinguished military career, he had fought in 18 battles, been wounded three times and taken prisoner once.
Union cavalryman Jack Williams (left) fought in 18 battles and was wounded three times and taken prisoner once. He was later revealed to be Frances Clalin a mother-of-three from Illinois
So it would come as quite a surprise when this prime example of a Union man was revealed to be a woman.
For Jack Williams was actually mother-of-three Frances Clalin - an Illinois-born farmer's wife who had enlisted alongside her husband back in 1861.