In the book Gates of Fire, it's mentioned that split pieces of wood were used as "dog tags" for soldiers. Each solider would write his name on the stick, break

In the book Gates of Fire, it's mentioned that split pieces of wood were used as "dog tags" for soldiers. Each solider would write his name on the stick, break it in half, toss one half into a basket and tie the other stick to themselves. At the end of the battle, any stick still in the basket that wasn't claimed was clearly a "casualty". The sticks tied to the individuals could also be used for identification.