Grimoald (died 725) was the duke of Bavaria from about 715 to his death. He was the youngest of the four sons of Theodo of Bavaria

Theodo of Bavaria

Theodo also known as Theodo V and Theodo II, was the Duke of Bavaria from 670 or, more probably, 680 to his death.It is with Theodo that the well-sourced history of Bavaria begins...

 and his wife Folchaid and the uncle of Swanachild

Swanachild

Swanachild was the second wife of Charles Martel, who brought her back from his first campaign in Bavaria in 725, along with her uncle Grimoald's wife, Biltrude. Swanachild belonged to the clan of the Agilolfings though her parentage is not quite clear...

, the second wife of Charles Martel

Charles Martel

Charles Martel , also known as Charles the Hammer, was a Frankish military and political leader, who served as Mayor of the Palace under the Merovingian kings and ruled de facto during an interregnum at the end of his life, using the title Duke and Prince of the Franks. In 739 he was offered the...

. At first, he co-reigned with his brothers Theodbert

Theodbert of Bavaria

Theodbert was the duke of Bavaria in some capacity or other from 702 to his death. He was the eldest son of Duke Theodo of Bavaria and Folchaid. He was first associated with his father as duke in 702, ruling from Salzburg...

, Theobald

Theobald of Bavaria

Theobald was the duke of Bavaria from at least 711, when his father Theodo associated him with his rule at Passau or Salzburg. He was the second son of Theodo and Folchaid....

, and Tassilo II

Tassilo II of Bavaria

Tassilo II was a ruler in southern Germany.He was the son, probably third, of Theodo of Bavaria and Folchaid. Sometime before 715, Theodo divided his duchy and associated with its rule the eldest two of his four sons. The eldest, Theodbert, was co-ruling as early as 702 and the second, Theobald,...

 and then, from around 719, alone. His father divided the principality, after involving his two eldest sons with the reign of the duchy in 715. Upon Theodo's death in 716, the divided duchy was plunged into civil war and all the brothers save Grimoald were dead by 719. It is not certain if the division of the duchy was territorial or a powersharing scheme, but if the former, it seems most probable that Grimoald's capital was either Freising

Freising

Freising is a town in Bavaria, Germany, and capital of the district Freising. Total population 48,500.The city is located north of Munich at the Isar river, near the Munich International Airport...

, which he later favoured as a diocesan seat, or Salzburg

Salzburg

-Population development:In 1935, the population significantly increased when Salzburg absorbed adjacent municipalities. After World War II, numerous refugees found a new home in the city. New residential space was created for American soldiers of the postwar Occupation, and could be used for...

, which he later treated as a capital of sorts (Vita Corbiniani).

It was Grimoald who induced Saint Corbinian to come to Bavaria in 724 to evangelise. Grimoald had married his brother's widow, Biltrude (Pilitrud), and by canon law this was incest. Corbinian promptly denounced the duke, who had already repented and relapsed. His anger was now raised and Corbinian had to flee. The next year (725), Charles Martel marched against Bavaria and carried off Biltrude and Swanachild, killing Grimoald in battle.