Question regarding translation

[sahartung]

Hello,

I have several documents where the last name of my father's family is spelt with a i or an o at the end (Gasparrini, Gasparrino). Is there a correct one to use or does it really matter?

Maybe a silly question but interested in what it was originally?

Thank you for your help,
Sharon

[PippoM]

Italian surnames were not "formally" defined until about 1900.
I mean that there was no rule, it was only the use that "made" the surname.
One person could be mentioned, along his life, with different forms of the surname, even in the same document.
They were often even "declined". For instance if someone was called "Rosso", his daughter could be "Rossa", and his children all together "Rossi". Then, when one of such versions was formalized by some clerk or priest, it took on the modern "fixed" form.
So, the answer is, to me: there's no correct use and it doesn't really matter.

[sahartung]

Thank you. Makes sense.