I'm only joking a little. Funny thing, surnames aren't actually that old for Europeans. Most of history there'd be maybe two people with the same name. They solved it back then very much the same way we solve it now.
Funnily enough, my "full id" (full name, city, profession plus year) isn't unique to me unless you add a date of birth.
Maybe it's not unique with a date of birth either, but statistically it should be.
It's a regional thing, but roughly translates to "John Smith, programmer from NY, born 1995"
Serial Number = was supposed to be what order the things were made in (e.g. the number of the serial order), but this is often obfuscated or often repeats [1].
In cars, make would be like Ford. Model would be like Focus, serial number would be VIN (vehicle identification number - in cars, those are generally unique!).
Ford Focus + VIN, basically.
There is a theoretical concept of a unique identifier for everything... including people from ISO under ISO 8000.. combining a natural location identifier (eNLI)[2] and an ISO8601 timestamp - to represent "where and when a thing is considered to be born" - a point in time and space the thing is considered to come into existence.
I think the idea is called "natural person identifier" for humans.
This ID has to be assigned but I think you can see the idea at least.
I suppose this doesn't include make/manufacturer but realistically that isn't needed for uniqueness in this scheme, only as descriptive metadata for things that have one.
[1] This is related to the fact that if serial numbers were truly serial, one could estimate the rate and quantity of production which is considered sensitive information by most manufacturers. This relates to "the German tank problem" - during WWII the allies were able to accurately estimate the production of German tanks by analyzing the serial numbers off captured tanks.
(No racist intentions here, but you bring up both points and I thought that to be interesting)