I don't know of about the treaty of Versailles, but the practice of assigning monetary values to people's lives for purposes of calculating compensation due is ancient indeed.
One of the oldest known bodies of law, the Code of Hammurabi, contains a large number of instances of payments/punishments required in recompense for infractions, with the amount or severity determined by the relative social positions of the offender and victim. The most famous portion of this is:
"Ex. Law #196: "If a man destroy the eye of another man, they shall destroy his eye. If one break a man's bone, they shall break his bone. If one destroy the eye of a freeman or break the bone of a freeman he shall pay one gold mina. If one destroy the eye of a man's slave or break a bone of a man's slave he shall pay one-half his price."
Another example is the concept of "weregild", a concept in Salic, Scandinavian and Germanic law, whereby the victim's family would be paid a sum based on the slain person's status, property and wealth. This is a more likely predecessor to the modern system of restitution due to the Germanic Law's place as an ancestor and inspiration for the English Common Law, which is widely used in the US and UK, as well as other locations in the British Commonwealth.