The Vita Sancti Arnulfi (c. 657), written shortly after Arnulf's death, states that he was of Frankish ancestry, from "sufficiently elevated and noble parentage, and very rich in worldly goods".

[1] Tenth- and eleventh-century texts like Genealogiae Breves Regum Francorum often claim that Arnoald was Arnulf's father, but this is considered a fabrication.

[2] Medieval Frankish historians Patrick Geary and Richard Gerberding observe that the lack of contemporary written texts makes it impossible to trace Arnulf's ancestry.

Paul the Deacon's Liber de episcopis Mettensibus (c. 784) presents Arnulf as Charlemagne's third great-grandfather, while Annales Mettenses Priores (805) depicts him as only a "close relative.

[12] Arnulf married in 596 to a noblewoman whom later sources identify as Dode or Doda (born c. 584), the paternal aunt of Saint Glodesind of France, an abbess of a monastery in Metz.

[12] Chlothachar, who appreciated Arnulf's administrative skills, offered him the vacant see of Metz, the capital of the Austrasian kingdom.

The revolt led to her overthrow, torture and eventual execution, and the subsequent reunification of Frankish lands under Chlothachar II.

[16] At the moment Arnulf resigned as bishop, a fire broke out in the cellars of the royal palace and threatened to spread throughout the city of Metz.

At the point when the exhausted procession was about to leave Champigneulles, one of the parishioners, Duc Notto, prayed "By his powerful intercession the Blessed Arnold will bring us what we lack."

Immediately the small remnant of beer at the bottom of a pot multiplied in such amounts that the pilgrims' thirst was quenched and they had enough to enjoy the next evening when they arrived in Metz.