a religious order, so called from their founder Peter de Mounon, afterwards Pope Celestine V. He was born of humble parents at Hernia in the kingdom of Naples in 1215; and retired while very young to a solitary mountain, in order to dedicate himself to prayer and mortification. The fame of his piety soon attracted followers; and with these in 1254 he formed a kind of community, which ten years later was approved by Pope Urban IV. and erected into a distinct order, called the Hermits of St Damien. Peter de Mounon governed this order till 1286, when his love of solitude induced him to quit the charge. In July 1294 he was raised to the pontificate by the name of Celestine V. By a bull he approved of the constitution of the Celestins, and confirmed all their monasteries to the number of twenty. After governing the church but five months and a few days, he found that he was unequal to the burden, and renounced the pontificate in a consistory held at Naples.

After his death, which happened in 1296, the Celestins made great progress, not only in Italy, but likewise in France, whither in 1300 the then general, Peter of Tivoli, sent twelve religious persons at the desire of Philip the Fair, who gave them two monasteries; one in the forest of Orleans, the other in the forest of Compiegne. This order also passed into several provinces of Germany. They possessed about ninety-six convents in Italy, and had twenty-three in France at the time of their suppression in 1778.

The Celestins rise two hours after midnight to say matins; eat no flesh except when sick; and observe frequent fasts. Their habit consists of a white gown, a capuche, and a black scapulary. In the choir, and when they leave the monastery, they wear a black cowl with the capuche.