|Mayor of the palace|
|Issue||Childebert the Adopted|
|Father||Pepin of Landen|
|Mother||Itta of Metz|
With the death of Pepin in 640, Grimoald became the head of his household, the most powerful in Austrasia. At this time, Radulf, Duke of Thuringia, rebelled against Sigebert III, king of Austrasia. Grimoald participated in the ensuing expedition against the insurrection, but it was a failure. Nevertheless, Grimoald succeeded in saving the life of the king and became his close friend. Then, by removing his rival, Otto, he took over the position which his father once held.
Grimoald convinced the childless Sigebert III to adopt his son, named Childebert at his baptism. Sigebert eventually had an heir, Dagobert II, but upon his Sigebert's death in 656, Grimoald had the young Dagobert exiled to Ireland and put his son on the throne.
- Richard Gerberding, The Rise of the Carolingians and the Liber Historiae Francorum
- Christian Settipani, La Préhistoire des Capétiens (Nouvelle histoire généalogique de l'auguste maison de France, vol. 1), 1993 (ISBN 2-9501509-3-4)
- Alban Butler's Lives of the saints, edited, revised and supplemented by Thurston and Attwater. Christian Classics, Westminster, Maryland
- Bennett, S.A., "Grimoaldus (1)", A Dictionary of Christian Biography, Murray, 1877
- Liber Historiæ Francorum 43, MGH SS rer Merov II, page 316.
- R. P. Vincent, Histoire fidelle de st Sigisbert: XII roy d'Austrasie et III du nom; avec un abrégé de la vie du roy Dagobert, son fils: le tout tiré des antiquités austrasiennes
- Spiritual Kinship As Social Practice: Godparenthood and Adoption in the Early Middle Ages by Bernhard Jussen