Radoald (died 651) was the duke of Benevento (the southernmost Lombard

Lombardy

Lombardy is one of the 20 regions of Italy. The capital is Milan. One-sixth of Italy's population lives in Lombardy and about one fifth of Italy's GDP is produced in this region, making it the most populous and richest region in the country and one of the richest in the whole of Europe...

 duchy in medieval Italy

Italy

Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...

) from 646 to his death in 651. His elder brother, Aiulf

Aiulf I of Benevento

Aiulf I was the duke of Benevento from 641 to his death in 646 as the son and successor of Arechis I. However, he was mentally unstable and his adoptive brothers Radoald and Grimoald were regents for him. In 646, Slavic plunderers landed near Siponto on the Adriatic...

 was mentally unstable and Radoald and their younger brother Grimoald

Grimoald I of Benevento

Grimoald I was duke of Benevento and king of the Lombards .Born probably before 610 to Duke Gisulf II of Friuli and the Bavarian princess Ramhilde, daughter of Duke Garibald I of Bavaria, he succeeded his brother Radoald as duke of Benevento...

 were regent

Regent

A regent, from the Latin regens "one who reigns", is a person selected to act as head of state because the ruler is a minor, not present, or debilitated. Currently there are only two ruling Regencies in the world, sovereign Liechtenstein and the Malaysian constitutive state of Terengganu...

s. Radoald and Grimoald were brothers as younger sons of Gisulf II of Friuli

Gisulf II of Friuli

Gisulf II was the Duke of Friuli from around 591 to his death. He was the son and successor of Gisulf I.Gisulf and Gaidoald of Trent were at odds with King Agilulf until they made peace in 602 or 603. Gisulf also allied with the Avars to make war on Istria....

. They were adopted sons of Arechis I of Benevento

Arechis I of Benevento

Arechis I was the second duke of Benevento from 591 to his death in 641, a reign of half a century. He was from Friuli and was a relative of the dukes there, maybe a nephew of Zotto, his predecessor. He was appointed by King Agilulf in the spring of 591, after Zotto's death...

, of whom Aiulf was a son.

In 646, Slavic plunderers landed near Siponto

Siponto

Siponto was an ancient port town of Apulia in southern Italy. The town was abandoned after earthquakes in the 13th century; today the area is administered as a frazione of the comune of Manfredonia, in the province of Foggia...

 on the Adriatic. Aiulf personally led his forces against the intruders, but his horse fell into a pit dug by the Slavs around their camp and he was surrounded and killed. Radoald succeeded him with the support of King Rothari

Rothari

Rothari , of the house of Arodus, was king of the Lombards from 636 to 652; previously he had been duke of Brescia. He succeeded Arioald, who was an Arian like himself, and was one of the most energetic of Lombard kings...

. Radoald knew the Slavic language and induced them to depart. He was succeeded by Grimoald.