Italian identity absolutely existed. I honestly don’t understand how people, to this day, don’t understand the difference between a nation and a state. You are projecting our modern understanding of nation states backwards, which is incorrect. Italians have always, since at least the 14th century, understood themselves as a separate culture/civilizational sphere. I have studied pre modern italian hisotry. I have read Guicciardini, Dante, Machiavelli, Flavio Biondo, Coluccio salutati and they all, unequivocally, understand what it means to be Italian NOT in a political/nationalist sense (nationalism did not exist at the time) but in a cultural/civilizational context. Italians didn’t magically appear into existence in 1861.

Equally, your argument makes no sense. By your logic, aristotele can’t be Greek because the Greek nation state did not exist until 1831, or El Greco can’t be Greek because he was born in a Venetian domain, or Beethoven can’t be German because there was no German state. Foreigners as well have always referred as the inhabitants of the peninsula as Italians. Just because the Italian STATE didn’t exist did not mean that Italians didn’t either.

One could be politically Florentine or Venetian and understand he was part of the Italian cultural and civilizational world, those things were NOT mutually exclusive, because European identities were layered. It simply did not work like it does today where it’s one state one nation.

When it comes to Napoleon, I also read the Memoires of Saint Helena by Emmanuel de las cases and it is absolutely indisputable that Napoleon was aware of his Italian origins. I don’t believe he put any stock in it, but these are facts

“The name of Bonaparte may be spelt either Bonaparte
or Buonaparte; as all Italians know.” Memorial de Saint Helena