Prospero Caterini was an Italian cardinal.
Prospero Caterini was the son of Francesco Caterini and Maria Domenica Pacelli. His father's sister, Maria Antonia Caterini, had married Gaetano Pacelli, great-grandfather of Eugenio Pacelli, future Pius XII. The Caterini family would derive from the Cattanei of Gualdo Cattaneo, counts of Aversa in 1520, and would have changed surname by devotion to Saint Catherine of Alexandria. The Caterini were ascribed to the nobility of Nocera Umbra, Acquapendente, Onano and were awarded the title of counts by Pope Leo XIII.
Possession of the family was the castle of Santa Cristina in Grotte di Castro, near the lake of Bolsena, which also hosted the future Pope Pius XII when he was still a seminarian.
Prospero Caterini was an adviser to Pope Pius IX, who created him cardinal in the consistory of 7 March 1853, with the title of cardinal deacon of Santa Maria della Scala. He was apostolic protonotary, apostolic visitor to the pious house of the orphans and the monastery of Santi Quattro Incoronati, economic prefect of the Propaganda Fide, prefect of the Sacred congregation of the council, secretary of the "supreme SC and the universal and Roman inquisition", president of the commission of cardinals for preparation for the first Vatican council
He took part in the first Vatican Council and in the conclave of 1878 who elected Pope Leo XIII, of whom he was a close friend: it was he who announced his election as pontiff from the loggia of the basilica of St. Peter's.
He died in Rome on 28 October 1881 and his remains rest at the Verano cemetery in the sacellum of the Precious Blood archconfraternity.