Madelgisilus

Saint Madelgisilus (also called Maguil or Mauguille) was an Irish monk, friend and disciple of Saint Fursey, with whom he crossed to Picardy in France in the first half of the seventh century. After Fursey's death he withdrew among the monks of Saint-⁠Riquier.

Fearing that the esteem in which he was held in the monastery might lead him to pride, he obtained the abbot's permission and hid himself in the solitude of Monstrelet, on the river Authie, where he led a contemplative life. One source says he lived there with Saint Pulgan. He reposed around 655 (another source gives 685). His body was first buried in the chapel of the hermitage and later moved to a church built in his name near Saint-⁠Riquier.

He is commemorated on 30 May, held to be the day of his repose, as a saint of the West before the Great Schism (a saint of the undivided Church), by the New Calendar.