Saint Leontius of Autun (French:Saint Léonce) (d. ca. 430 AD) was a bishop of Autun in Gaul during the fifth century. He is mentioned in the Martyrologium Hieronymianum. He is sometimes confused with the similarly named Saint Leonorius (Saint Leonore, Lunaire)^[1] and Leontius of Fréjus who lived around the same time. He is venerated as a saint in the Catholic church, and his feast day is 1 July.

There are scant details of Leontius life before he entered the ministry, and almost no documentation.^[2] On 1 July, the Martyrologium Hieronymianum has the following listing, "The burial of Leontius, bishop of Autun (Gaul), 5th cent."^[3] The chronotaxis of the bishops of Autun show that he was the eighth bishop, serving after Evantius and before Euphronius.^[4]

It is believed he was born in Autun, entered the ministry and that he was the bishop of the Diocese of Autun in the 5th century.^[2] The diocese comprises what is now the French department of Saone et Loire, in the region of Bourgogne.^[5] He was a respected leader within the religious community of Gaul.^[2]

Leontius died circa 430 in Autun, and was elevated to sainthood pre-congregation.^[6] At the time of his death he was considered a confessor, and it was not uncommon for one who led a virtuous life who had died peacefully to be venerated as a saint.^[7][8] More than likely, he was elevated to sainthood by the local bishop.^[6] His cult spread throughout the region of Gaul where he lived, and he became a patron saint of Autun.^[2]

The French commune, Saint-Lieux-Lafenasse, is named after him (Languedocien: Sant Lionçe La Fenassa).^[9]

• Autun Cathedral

• (in German) Leontius von Autun
• (in Italian) Leonzio di Autun