Strands of Fading Suns
There are five major Noble Houses within the Known Worlds. There are:
These five houses were the ones that remained in power of the Emperor Wars and Vladimirs ascension to the throne.
There are also several minor houses, alomost all of whom owe some fealty to a major House. Each of these houses are detailed in Lords of the Known Worlds.
House Juandaastas mainly on Criticorum and Gwynneth
House Justinian mainly on Midian
House Keddah mainly on Grail
House Masseri mainly on Leminkainen and Cadavus
House Shelit on Hira
House Thana with no power base (Not even on Eridol)
House Torenson with no power base
House Trusnikron mainly on Ravenna and Cadavus
House Van Gelder mainly on Malignatus and Cadiz
House Xanthippes mainly on Luna, Holy Terra, Aragon, and Cadavus
There are more lesser houses, often only holding power on one world. Unlike the previous houses, there is little actual canonical information on these houses, beyond their names and where they hold fiefs.
Basque on Cadiz
Cameton on Byzantium Secundus
House Chauki on Iver
D’Rogue Glace on Rampart
The De Moley on De Moley
Dunama on Istakhr
Gilgar on Pandemonium
Lambeth on Byzantium Secundus
Ramakrishna on Hagard and Shaprut
Sacrananka on Byzantium Secundus
Setevis on Byzantium Secundus
Vasalayana on Leminkainen
There are three houses believed to have become extinct.