In the 580s, while Gundoald was trying to usurp the Frankish throne from the Merovingian monarchs, he appointed people to vacant offices within the territory that he controlled.
Therefore, when he found that the diocese of Dax was without a bishop, he appointed Faustianus, who was a priest.
The Merovingians had wanted to appoint a count named Nicetius as the new bishop.
[1] However, Gundoald lost the war and the territory was retaken by Guntram, a Merovingian king.
[2] Faustianus was deposed from his diocese and replaced with Nicetius; however, Bertram, Palladius and Orestes were ordered to supply him with food and one hundred gold pieces every year.