Balther was a monk of Säckingen educated at St Gallen under Notker, who in his wandering years found an old Life of Saint Fridolin in the Moselle valley, memorised it and rewrote it on his return home. He composed the Vita Fridolini and a liturgical office for the saint’s feast around 970, dedicating them to his old master; in the same year he became bishop of Speyer, where he died in 986 or 987.