The Great Houses of Serenno were composed of the wealthiest and most powerful families on the planet of Serenno and, it was rumored, the galaxy. Among these families were the Demici and Nalju families.
During the Clone Wars, the Great Houses supported Count Dooku and the Separatists. However, after the Clone Wars, Darth Vader was sent to Serenno by Palpatine to enact the retaliation of the Galactic Empire on the six ruling Houses, which had sided with the separatists during the war. During what was called the Cleansing of Serenno, a choice was offered to the five Counts, with the exception of Adan Dooku who was in exile during the Clone Wars: be killed by their oldest sons or be killed by the Sith Lord and his troopers. Rodas Borgin killed his father first followed by the others.
Following the assassination of Count Adan Dooku in 3 BBY, the Lords of the other Great Houses refused to elect Lord Borgin as regent. However, the Lords of the Great Houses elected Lord Orom Malvern as the new regent and Borgin's son, Pero, was named Lord of House Borgin.