The Occlusion Zone, also known as the Exclusion Zone, the Free Sectors, the Liberated Worlds, Nihil space or Nihil territory, sometimes abbreviated as the O. Z., was an area of space composed of ten sectors located in the Galactic Frontier within the Outer Rim Territories that was claimed by the Nihil and sealed away behind a barrier known as the Stormwall in 230 BBY. In 228 BBY, in response to an assault on the Stormwall by the Jedi Order and Galactic Republic, Eye of the Nihil Marchion Ro had the Occlusion Zone expanded to take more territory from the Republic, swallowing two entire sectors, several systems and planets, and bisecting the Seswenna sector just before reaching Eriadu. Following the escape of Jedi Master Avar Kriss from the Occlusion Zone, Ro had the Stormwall expanded a number of times in a manner that seemed haphazard and unpredictable to the Republic and the Jedi. The Occlusion Zone eventually expanded to engulf most of the Chommell sector of the Mid Rim, including the planet Naboo.