Birth. November 14, 1712, Rome. From a noble family. Son of Tommaso Antamori, consistorial advocate and rector of La Sapienza University from 1741 to 1747, and Elena Belloni.

Education. Studied at La Sapienza University, Rome, where he earned a doctorate in utroque iure, both canon and civil law, on September 26, 1737. Received the insignias of the clerical character, December 11, 1740.

Early life. Relator of the S.C. of Good Government, November 1737. Coadjutor of his father as consistorial advocate in 1741; succeeded him at his death in April 1751. In December 1751, he received the prelature called Abbreviatoris majoris presidentiae, which had as its charge the Congregation of S. Ivo and carried the category of abbreviatore di Parco Maggiore. Canon of the chapter of the basilica of S. Lorenzo in Damaso in July 1753. First assessor for the criminal of the auditor of the Apostolic Chamber in November 1753. Voter of the Tribunal of the Apostolic Signature of Justice in July 1758. Auditor of the prefect of the Fabric of Saint Peter's basilica in 1758. Referendary of the Tribunals of the Apostolic Signature of Justice and of Grace. Second lieutenant of the auditor of the Apostolic Chamber in July 1763; first lieutenant in October 1767, occupying the post until his promotion to the cardinalate. Examiner of the bishops elect. Rector of La Sapienza University, Rome, from September 1760. Received the minor orders on October 9, 1774; the subdiaconate on June 10, 1775; and the diaconate on June 1, 1776. Assessor of the Supreme S.C. of the Roman and Universal Inquisition and canon of the patriarchal Vatican Basilica from April 1775. Protonotary apostolic supernumerarium in November 1775.

Cardinalate. Created cardinal priest in the consistory of December 11, 1780; received the red hat on December 14, 1780; and the title of S. Alessio on April 2, 1781. Ascribed to the SS. CC of Bishops and Regulars, Council, Religious Immunity, and Indulgences and Sacred Relics. Protector of the cities of Foligno and Orvieto; of the Opera Pia di S. M. della Stella in the cathedral of Orvieto; of the Noble Congregation of S. Biagio in the city of Orta; of the city of Orta; of the shrine of Mongiovino; of the Confraternity of the Suffragio della Terra di Monte Castello di Todi; and of the chapter of Bagnorea.

Episcopate. Elected bishop of Orvieto, December 11, 1780, with dispensation for not having been ordained a priest. Consecrated, February 11, 1781, Rome, by Cardinal Henry Benedict Mary Stuart, duke of York.

Death. December 4, 1795, Orvieto. Exposed and buried in the cathedral of Orvieto.

Bibliography. Moroni, Gaetano. Dizionario di erudizione storico-ecclesiastica da S. Pietro sino ai nostri giorni. 103 vols. in 53. Venezia : Tipografia Emiliana, 1840-1861, II, 161; Notizie per l'anno MDCCXCV. In Roma MDCCXCV : Nella Stamperia Cracas, presso la fine del Corso, p. 14; Ritzler, Remigium, and Pirminum Sefrin. Hierarchia Catholica Medii et Recientoris Aevi. Volumen VI (1730-1799). Patavii : Typis et Sumptibus Domus Editorialis "Il Messaggero di S. Antonio" apud Basilicam S. Antonii, 1968, pp. 33, 41 and 426.