Jonathan was the Duke of Gaeta from 1112 until his death. He was a member of a cadet branch of the Drengot family

Drengot family

The Drengots were a Norman family of mercenaries, one of the first to head to the Mezzogiorno of Italy to fight in the service of the Lombards. They became the most prominent family after the Hautevilles.-Origins:...

 then ruling in Capua

Principality of Capua

The Principality of Capua was a Lombard state in Southern Italy, usually de facto independent, but under the varying suzerainty of Western and Eastern Roman Empires. It was originally a gastaldate, then a county, within the principality of Salerno....

. He was a grandson of Bartholomew, Count of Carinola. He was a minor when granted Gaeta in 1112. He was under the regency of his uncle, Richard of Carinola

Richard III of Gaeta

Richard III , also known as Richard of Caleno, was the Count of Carinola last independent Duke of Gaeta, ruling from 1121 to his death. He was a son of Bartholomew of Carinola and a member of the Drengot family. From 1112 he was regent for his nephew, Jonathan; in 1121 he succeeded him...

. He died a minor in 1121 and was succeeded by his uncle.

Sources

• Skinner, Patricia. Family Power in Southern Italy: The Duchy of Gaeta and its Neighbours, 850-1139. Cambridge University Press: 1995.