Grifo was the illegitimate son of Charles Martel, an important leader of the Franks.
After the death of Charles Martel power may well have been intended for his illegitimate son, Grifo, as well as Pippin (the Short) and Carloman, Martel's legitimate children. He was lured into a trap by his half-brothers, however, and imprisoned in a monastery.
On his escape in 747, Duke Odilo of Bavaria gave his support to Grifo. Duke Odilo died a year later, providing opportunity for a decisive intervention by Pippin the Short. Odilo's infant son, Tassilo, was imposed as a subordinate duke.
Grifo and his supporters continued to resist until he was killed in 753.
After the death of Charles Martel power may well have been intended to be divided among Grifo and his half-brothers Pippin the Younger (Pippin the Short) and Carloman.
Grifo, considered illegitimate by Pippin and Carloman, was lured into a trap by his half-brothers, however, and imprisoned in a monastery.
Grifo continued his rebellion, but was eventually killed in the battle of Saint-Jean de Maurienne in 753, while Pippin became king of the Franks as Pippin III in 751.