I was reminded of dog tags when I heard R. Lee wassisname mention them on a promo for his show “Mail Call” on cable. I never, ahem, get a chance to watch the show so I didn’t see him answer the question on what exactly they were for.
When I was in the USN, popular lore was that if you died in the field (in battle) someone would drive one between your upper front teeth as id for the body and take the other one back. Somewhere.
Any corpsmen or medics know the straight dope?
Peace,
mangeorge
C/S
In fact, each dog tag (we were issued 2) had a small notch in it just for the purpose you state.
According to R. Lee Ermy, the notch was for nothing more than to align the tag on the stamping machine.
He also mentioned that many military personnel lace a dog tag in their boots, because “Sometimes, that’s all there is left.”
I gotta tell ya, Monty, I was a little hesitant to click that link. But thanks.
There were about a million (900) Marines aboard my ship in Viet Nam, and they really liked to bullshit the swabs. 
Let me tell you about the VC “head” sometime.
Glad to help, mangeorge. Your use of the phrase “corpsman or medic” above reminded me of a MAS*H episode I just saw a couple of days ago. Hotlips is screaming “Corpsman!” to get someone over to help her. My thought was, “Of course, nobody’s running over. All she’s got around her are Medics!”
Okay, now that I’ve told you that one–'fess up with the VC head story.
Straight Dope Staff Report What’s the origin of army dog tags?
Ok, Monty. It has a sad part.
The famous USS Ogden VC Head;
One of the Marines, called Red, came back from an operation (battle) with one of those little bags that look like netting. In it was something round, about the size of a cantalope, wrapped in the famous VC “pajama” cloth. Only it had ‘bumps’ on it. These bumps were about where you’dexpect to see a nose and ears, but Red told everybody it was just a melon. When he said “melon”, he’d wiggle his eyebrows and giggle. I mean chuckle, Marines don’t giggle. Anyway, all his buddies swore it was a VC’s head, and that Red had used his K-Bar to obtain it. He took this thing everywhere, and carried it around for weeks. He’d leave it in the open and walk away a little, daring one of us to take a look. Nobody did. Ever.
Sad part;
Red went over once too often and didn’t make it back. His mates brought the bag topside and we gave it a burial at sea. Nobody looked.
Marines do cry.
Peace,
mangeorge
I have my father’s ID/dog tags from WWII. They have a notch. My tags from the Vietnam period are smooth with no notch.
The tags came with a chain, really two chains, one long one strung through one tag and worn around the neck like a necklace and a second short chain to secure the second tag to the long chain. One tag stayed with the corpse and the other went in the small sack with personal effects. How the tag was secured to the corpse was up to the graves registration people. I suspect they used safety pins if nothing else worked.
People who worked around machinery did not wear the tags around the neck. There was too much danger that the chain would catch on something and pull your face right into a rotating part. Better to string them through a button hole and wear them inside your blouse and out of the way.
Israeli soldiers are issued two dogtags - one is kept on a chain around the neck, the other is split into 2, with each half slipped into a special compartments in the top of their boots.
BTW, the neck tag is always completely covered with a dark cloth or leather sheath, and the chain is pushed through para cord; the logic being that having pieces of metal glinting at the nape of your neck could be considered poor fieldmanship. In addtion, lots of guys also attach other stuff to their tags, such as whistles, scalpels, pictures of their girlfriends and/or several verses of Psalms (for those so inclined).
Canadian dog tags are one piece (two almost identical halves), with a notch between them for easy breaking (to take one of the halves back, leaving one with the body).
I say almost identical because one has “do not remove” stamped into the back.
They look sort of like this -Canadian Style Dog tags