During the American Civil War many soldiers were afraid no one would be able to identify them if they died and were horrified at the thought of being buried in unmarked graves.
So, some pinned on paper tags, scratched their names onto the back of their belt buckles or carved their names into wooden discs which they hung around their necks.
But the origins of identification tags began much earlier.
There are records of second century Spartan soldiers writing their names on sticks which they tied to their left wrists. Roman legionaries were given a "signaculum", a lead disc on a leather string with their name and legion identification when they enlisted.
Jump to the 20th century.
The British Army introduced aluminium identity discs in 1907, two to be issued to each soldier.
These were later replaced with tags made of vulcanised asbestos fibre, more comfortable to wear in hot climates.
The first tag, an octagonal green disc, was attached to a long cord around the neck.
The second tag, a circular red disc, was threaded on a six-inch cord suspended from the first tag.
In the case of a fatality, the first tag was to remain on the body for future identification, while the second tag could be taken to record the death.
During World War II, Whanganui resident Josephine Ruth Duncan trained as an ambulance driver in London and was eventually posted to Egypt and served on the hospital ship Oranje.
The Whanganui Regional Museum has her identification tags in its collection.
They are made of pressed leather.
There is a green octagonal tag with two holes and a circular red tag with one hole. Both communicate her serial number, country, religious affiliation, blood type and name. 8160366 / NZ / C OF E / O / J R DUNCAN.
But it's not only soldiers who were issued with tags.
Another tag in the museum collection is a tear-drop shaped alloy tag inscribed with a name, school and address SHAUN / REILLY / 5 / HUTCHINSON / ST / W-NUI / ST. JOSEPH SCHOOL with a small circular hole at top. Shaun donated his tag to the museum in 2000 and told us its story.
"During the war years of 1939-45, I was a pupil at the Villa Maria School of the Catholic Church in Wanganui. The threat of a Japanese invasion was very real and to identify children in case of attack, Catholic school children were issued with dog-tags with personal information imprinted, to be worn at all times. Mine has survived for 60 years. I thought it was worth preserving so I am giving it as a present for the museum. It may be the only one in existence."
Skip now to the 1950s and to the US. The threat of a nuclear war with Russia prompted schools to issue every pupil with a metal military-style dog tag with the child's name, address and blood type. The purpose was to help identify the children's charred remains after a nuclear explosion. It was the era of "duck and cover" and children were on the front lines.
Considerable technological advances have arrived since World War II, including the ability to use DNA to identify remains. But despite these advancements, dog tags are still issued to service members today.
•Kathy Greensides is collection assistant at Whanganui Regional Museum.