In my experience with "named" horns, particularly more common horns, somewhere in the recent past an owner has checked military records, found a closely matching name, gathered information on that person from the internet, and assembled a "provenance" for the horn.
The major flaw in this approach is that there is no direct connection between the name on the horn, and the similar name in old records. In truth, there are usually other individuals with similar names living at about the same time that could have been the owner, but usually the one with the most historic interest, i.e., military service, is presumed to be the owner and selected for the "provenance." There is always a chance they got the right person, but there's a better chance they did not due to their biased selection process. No "provenance" is really a provenance unless there is documentation that traces/links the horn back to its original owner, making a real connection. A lot of today's provenances are more wishful thinking than established fact, yet they are presented to potential buyers as "fact" while omitting the "minor" detail that there is no documented connection to the presumed original owner.
Shelby Gallien