Spanish Translation
¿Cómo dice?
"In the Middle Ages, in Italian, LEI didn’t exist and the only two existing forms were TU and VOI (in fact, Dante, in the Divine Comedy, used TU with the people he already knew and VOI with the powerful people he didn’t know).
LEI was used only starting from 1500 as an extremely formal form reserved to powerful people who deserve respect. The spread of the use of Lei seems to come from the Spanish influence in the Italian peninsula.
During the Fascist regime, Mussolini decided to ban the use of Lei because of it being foreign and not “manly”. So he imposed the use of VOI and restored what he thought the true Italian character was.
However, what really matters is that, after the fall of the Fascist regime, VOI used as a courtesy form towards a single person has become extremely rare and you might hear it only in the South of Italy and only among old people.
Therefore, the answer to the question whether it is better to use Lei or Voi is: it should always be better to use Lei."
(source: COURTESY pronoun in Italian: LEI or VOI? – LearnAmo)