Grimoald I was duke of Benevento and king of the Lombards.
Background
Grimoald was probably born before 610 to Duke Gisulf II of Friuli and the Bavarian princess Ramhilde, daughter of Duke Garibald I of Bavaria. In 641–42 Civil Engineering, he and Radoald had served as regents for their mentally incapable adoptive brother, Duke Aiulf I. Grimoald married the princess Theodota, daughter of King Aripert I. Their son was Garibald.
Career
His martial prowess and skill in the field of battle secured his victory in many border wars. Romuald then took Taranto and Brindisi, much limiting the Byzantine influence in the region during the rebellion of Mezezius in Sicily, which had distracted the Byzantines after Constans" death. His capture of Forlì was shameful, however, for he took it on Easter Day, slaughtering worshippers during the festivities.
While he was combatting the Byzantines in the Mezzogiorno, he left Duke Lupus of Friuli as regent in the north.
Lupus usurped all authority and rebelled, though he was crushed and, with the help of the Avars, his duchy despoiled and devastated. Grimoald tracked down Lupus" aspiring son Arnefrit, and his Slav allies, and defeated him at Nimis.
Arnefrit died in battle. Grimoald placed Wechthari, a stalwart enemy of the Slavs, in Friuli.
Grimoald defeated the Franks, who invaded during the infancy of Chlothar III. Grimoald had allied with Perctarit at Asti and the Avars, of whom he had been a hostage in his youth.
He saved the northeast of Italy by defeating the Slav tribes and maintained internal order by suppressing the baronial revolts and autonomy of the duchies of Friuli and of Spoleto, where he installed Thrasimund. However, he perceived Saint Michael — whose cult was spreading strongly from Monte Gargano— as the warrior-protector of the Lombard nation. He died in 671 after concluding a treaty with the Franks and was succeeded by Perctarit, whom he had exiled.
He was a popular ruler, known as much for the kingly virtues of generosity and mercy as for his ferocity and ruthlessness in war.