Sergius V was the son and successor of John V

John V of Naples

John V was the son and successor of Sergius IV as Duke of Naples from 1034 until his death.In 1034 Pandulf IV of Capua instigated a revolt in Sorrento and annexed it to Capua. In the same year, Sergius IV's sister died and her husband, Rainulf Drengot, returned to Pandulf's allegiance...

 as Duke of Naples from 1042 to 1082.

In Summer 1074, hostilities flared up between Richard I of Capua

Richard I of Capua

Richard I Drengot was a count of Aversa and prince of Capua .He was the son of Asclettin, count of Acerenza, younger brother of Asclettin, count of Aversa, and nephew of Rainulf Drengot, the Norman adventurer who had first travelled to southern Italy in 1017 and progressed to set up the first...

 and Robert Guiscard

Robert Guiscard

Robert d'Hauteville, known as Guiscard, Duke of Apulia and Calabria, from Latin Viscardus and Old French Viscart, often rendered the Resourceful, the Cunning, the Wily, the Fox, or the Weasel was a Norman adventurer conspicuous in the conquest of southern Italy and Sicily...

. Sergius allied with the latter and made his city a supply centre for Guiscard's troops. This pitted him against Aversa

Aversa

Aversa is a town and comune in the Province of Caserta in Campania southern Italy, about 15 kilometres north of Naples. It is the centre of an agricultural district, the agro aversano, producing wine and cheese...

 and Capua

Capua

Capua is a city and comune in the province of Caserta, Campania, southern Italy, situated 25 km north of Naples, on the northeastern edge of the Campanian plain. Ancient Capua was situated where Santa Maria Capua Vetere is now...

, while Richard I was supported by the pope. Sergius soon opened negotiations with Pope Gregory VII

Pope Gregory VII

Pope St. Gregory VII , born Hildebrand of Sovana , was Pope from April 22, 1073, until his death. One of the great reforming popes, he is perhaps best known for the part he played in the Investiture Controversy, his dispute with Henry IV, Holy Roman Emperor affirming the primacy of the papal...

, as he had barely escaped destruction in June. These negotiations were concurrent with those of the two Norman

Normans

The Normans were the people who gave their name to Normandy, a region in northern France. They were descended from Norse Viking conquerors of the territory and the native population of Frankish and Gallo-Roman stock...

 princes, mediated by the abbey of Montecassino.

Sources

• Chalandon, Ferdinand. Histoire de la domination normande en Italie et en Sicilie. Paris
  Paris
  Paris is the capital and largest city in France, situated on the river Seine, in northern France, at the heart of the Île-de-France region...
  
  , 1907.