Grimoald I (616–657), called the Elder (in French, Grimaud l'Ainé), was the mayor of the palace of Austrasia from 643 to his death.
[2][3] 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.
[4] Grimoald convinced the childless Sigebert III to adopt his son, named Childebert at his baptism.
[7] Grimoald was eventually captured and executed by the king of Neustria—either Clovis II or his son and successor, Chlothar III.