Filippo Antonio Gualterio (24 March 1660 – 21 April 1728) was made a papal nuncio to France (1700–1706) and a cardinal of the Roman Catholic Church from 1706.
Life.
Descended from the ancient Gualterio family of Orvieto related to Pope Innocent X, he was the uncle of Cardinal Luigi Gualterio.
Born at Fermo, whose archdiocese was governed by his grand-uncle Cardinal Carlo Gualterio, he was the eldest of 17 children of Stanislao Gualterio, "Gonfaloniere" of Orvieto, and Anna Maria Cioli, noble of Todi. He received doctorates at the University of Fermo in philosophy, theology, and "utroque iure", both canon and civil law.
In France.
Beginning in 1685, when he was made Governor of San Severino, he served in various governorates of the Papal States until he was sent as Vice-legate to Avignon (1696–1700), where he carried himself so well he was made papal nuncio to the court of King Louis XIV of France in April 1700, in preparation for which he was made titular archbishop of Atena at the end of March. On 16 May 1700, he was consecrated bishop by François de Mailly, Archbishop of Arles. Another member of his family, Sebastiano Gualterio, had already served as nuncio to France in 1554. 
An avid collector, in 1715 he became an honorary member of the Académie des inscriptions et belles-lettres, and was a regular visitor to François Roger de Gaignières. He amassed a library of 10,000 to 12,000 rare volumes, which was purchased by Cardinal Corsini, who incorporated it into his own, and who, having become Pope under the name of Clément XII (1730), made it accessible to the public. He befriended Louis de Rouvroy, duc de Saint-Simonand, according to Boislisle, they maintained an encrypted correspondence that has now disappeared, probably destroyed at the Duke's request. Many of his letters are preserved in the British Library (London). 
During his nunciature he established ties with prominent members of the European nobility and, in particular, with the Duc of Saint-Simon, who often mentions him in the "Memoirs". In recognition of the esteem he gained from King Louis XIV, he was named the commendatory abbot of the Abbey of Saint-Remy in Rheims (1710) and of the Abbey of Saint-Victor in Paris (1713 or 1714).
Gualterio was transferred to the bishopric of Imola in 1701, with the personal title of archbishop. He was recalled from Paris to be created cardinal in the consistory of 17 May 1706 and sent as legate to Romagna, 25 June. He returned from his nunciature in Paris and arrived in Imola in December 1706, but did not stay long.
He was cardinal-priest of St. Chrysogonus in 1708, then of Santa Cecilia in Trastevere in 1724, and finally of Santa Prassede in 1726.
Gualterio was nominated Cardinal Protector of Scotland, as of 1706, and England, as of 1717, he was one of the closest advisers to the Stuart Pretender, James Stuart, the would-be James VIII of Scotland, who conferred upon his brother Giovanni Battista the Jacobite title of Earl of Dundee.
In 1709 Gualterio was transferred to the Diocese of Todi, with the personal title of archbishop, later resigning the see in favour of his brother, Ludovico Anselmo Gualterio, 5 December 1714. He participated in the Papal conclave, 1721, which elected Pope Innocent XIII and in the conclave of 1724, which elected Pope Benedict XIII.
Founder of a monumental library, now part of the Accademia dei Lincei, and of a vast collection of art, which after his death was partly acquired by Hans Sloane and is now at the British Museum.
Gualterio's remains were transferred to the tomb of his family in the Chapel of the Madonna di San Brizio in the Cathedral of Orvieto, alongside his uncle Gianotto Gualterio, his great-uncle Carlo, both archbishops of Fermo, and his brother Ludovico Anselmo, bishop of Todi. The Gualterio papers are conserved at the British Library.
References.
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