After the death of his brother, John IV in 1008, his mother took over the regency for her grandson, Leo's nephew, John V. Leo challenged his mother for the regency, successfully displacing her by 1017.
The fisheries owned by the duke on the island of Ventotene and Santo Stefano in the Pontines were granted to Kampulus.
[2] There is a single document from 1023 in which Leo and Emilia are listed together as regents, but it comes from the autonomous county of Suio and may not represent the facts on the ground.
The conflict between Leo and Emilia was devastating for Gaeta's influence in the region.
The counts of Traetto ceased to recognise Gaetan sovereignty around this time, as did the area of Sperlonga.