What is the purpose of the military dog tag chain?

The purpose of the dog tag is so a solider can be ID if needed. There are 2 of the ID tags so one can be put into the mouth of the body and one taken away for further ID. In the civil war the men would write their names on a piece of paper and pin them to their clothing so if they died in battle they would know who they were. Today in the Middle East many people have their names tattooed on their body someplace for the same reason .

During WWII, marines in the Pacific would take one tag for ID, and yes, put the other in the soldiers mouth. Direct quote from my Uncle Jim who was taught that during that war and when i questioned it during my Nam tour, they said the same thing...inside the mouth! Gross but true