Salerno was a Lombard Principality in southern Italy in the latter centuries of the first millenium.
When Prince Sicard of Benevento was assassinated by Radelchis in 839, the people of Salerno promptly proclaimed his brother, Siconulf, prince. War raged between Radelchis and Siconulf until Emperor Louis II, King of Italy, came down and forced a peace in 851, confirming Siconulf as prince of Salerno. The chronology is very confusing from then on until the assassination of Adhemar, when a new dynasty took the throne.
The Principality of Salerno reached its zeniht under Guaimar IV, who ruled all continental southern Italy between 1039 and 1048, expelling for the first time since the fall of the western Roman empire the Byzantines from the Italian peninsula.
^In the 19th century, Michelangelo Schipa, relying on an 11th-century charter mis-dated to 917, inserted a fifth prince named Guaimar into the list, suggesting this "Guaimar III" was a son of Guaimar II. This necessitated re-numbering Guaimar III as "Guaimar IV" and the actual Guaimar IV as "Guaimar V".[1]
^Also ruled Amalfi (1039–43), Gaeta (1040–41) and Capua (1038–47) .