Short answers, pulled from the story.
Pietro Ranzano was an Italian Dominican friar, bishop, historian, and humanist born in Palermo in 1428. He is best known for De primordiis et progressu felicis Urbis Panormi, a history of Palermo from its origins to the period in which he was writing, and for the Epitome rerum Hungarorum, a history of Hungary commissioned by Queen Beatrice of Naples.
Ranzano identified an inscription on a tower above the Porta Patitelli in Palermo as ancient Chaldean characters, and used it to argue that Palermo had Chaldean origins. The inscription was later discovered to be a forgery, making his conclusion erroneous, though his account remained valuable as a record of Sicilian intellectual thought near the time of the Jewish expulsion.
Around 1464, Ranzano was appointed papal nuncio in the kingdom of Sicily and was entrusted with organizing a crusade against the Turks, which involved preaching and collecting funds for the campaign. He also taught at the Dominican College in Palermo during this period.
Isaac Guglielmo was a Pisan Jew who owned an ancient book that local Palermo Jews had described to Ranzano as evidence for the Chaldean inscription. He showed the book to Ranzano, providing the documentary corroboration that local Jewish memory alone could not supply.
In 1488, Ranzano was sent to Hungary as the envoy of the Kingdom of Naples to the court of Matthias Corvinus. Queen Beatrice of Naples commissioned him to write a history of Hungary; he completed it in one year under the title Epitome rerum Hungarorum, treating the Hungarians as descendants of the Huns and King Matthias as a second Attila.
Ranzano died in Lucera in 1492, the same year the Jews were expelled from Sicily, which marked the end of what historians describe as multicultural Sicily. His History of Palermo remains the only Sicilian historical account from that period to give significant attention to Jews and Jewish culture.