The Cleansing of the Nine Houses was one of the conflicts of the Old Sith Wars, occurring sometime before the Great Hunt. The details were lost to history, but it appears to have been a civil war in the Tapani sector. The Jedi Order and House Pelagia battled the Sith inspired Mecrosa Order of assassins, which was sponsored by House Mecetti. During the conflict, House Melissus and House Barong were absorbed by House Mecetti.