De Visdelou was born at the Château de Bienassis, Erquy, Brittany. He entered the Society of Jesus on 5 September1673, and was one of the missionaries sent to China by Louis XIVin 1687. He acquired a wide knowledge of the Chinese language and literature. Other learned Jesuits considered that he gave too much credit to modernChinese commentators, who being atheists and materialists read their own ideas into the ancient Chinese sages. When the papal legate Mgr. de Tournon came to China in 1705, chiefly to regulate the question of the Chinese Rites, Visdelou was the only Jesuit favourable to their prohibition. Tournon appointed him Vicar Apostolic of Kwei-chou with the title of bishop of Claudiopolis in Isauria, but his superiors opposed the nomination, since Visdelou had not received papal dispensation from his vow not to accept ecclesiastical dignity. With the missionaries who had submitted to the decree against the rites, Visdelou followed the legate to Macau, where he was secretly consecrated bishop, 2 February 1709. He then set out for Pondicherry where he arrived, 25 June 1709; he remained there in great retirement in the house of the French Capuchins until his death at Pondicherry.
Works
Visdelou took with him over 500 volumes in Chinese and almost his sole occupation consisted in working on these. He sent to Rome several writings on the questions of the rites. The Sinologist, James Legge, says he "was in the habit of writing extravagantly about the Chinese and caricaturing their sentiments". His most trustworthy works deal with the history of the Tartars. He collected from Chinese historians unique documents on the peoples of Central Asia and Eastern Asia: Huns, Tatars, Mongols, and Turks. His researches on this subject were first published as supplement to Herbelot's Bibliothèque orientale. However, they must have assisted Joseph de Guignes in his history of the Huns, for the geographer Anville who had handled all Visdelou's valuable manuscript on the Tatars tells us that the author had sent them to the Academician Jean-Roland Malet, who died in 1736.
