During the Civil war soldiers started sewing or writing their names into clothing, and sometimes purchasing tags from various suppliers to keep on themselves in case of death so that their body could be identified. identification of corpses was a large problem during the civil war. This practice continued thru the spanish american war.

ww1 dog tag set

The U.S. Navy used their own style dog tags from WW1 into the second world war. the first issue was acid etched onto a oval disc made of monel metal. this included the acid etched fingerprint of the sailor. They then sometime after the first world war changed over to a metal tag that was stamped with information and no fingerprint. these were used up until the end of the war when they also went to the Notched style tags.

during vietnam the use of "silencers was allowed to keep the dog tags quite while in the jungle. also during this time in the 1960's we saw the introduction of the modern dog tags which simply didn't have the notch in them due to the discontinuance of the model 70 Addressograph medical imprinter.

the serial numbering system changed over to the soldiers social security number in 1969. soldiers were issued a serial number but their social security number was used on the tags.

Today not only does the military still use dog tags but they have become a fashion item among children to adults, used as medical alert tags, and yes you can even use them for your dog!