Located in an impenetrable cosmic dust cloud ominously referred to as the Cloak of the Sith, easily navigable routes to Roon had long been lost. Even the most complete accounts, located in the Baobab Archives on Manda, were sketchy at best, and the lockdown of information following the rise of the Galactic Empire seemed to seal Roon's fate as a planet lost to history. This was fine to native Roonians; the planet was largely self-sufficient and plentiful in resources.
Surrounded by a lethal ring of asteroids and meteors, Roon was located in an Outer Rim Territories system of the same name. Other notable planets in the Roon system included the searing rock planet of Kaloo (which was moonless) and the barren rock world Iqoon (which had two moons).
Like nearby Ryloth, Roon only rotated on its axis once every orbit around the sun, rendering one side constantly bright and the other side constantly dark. Unlike Ryloth, however, the lit side of the world was not scorching, nor was the dark side frigid; this phenomenon may be due to cloud cover, or an extensive ozone layer. Whatever the reason, Roon long served as a staging point for spice smugglers coming from Ryloth.
The way to Roon was rediscovered by explorer and treasure-hunter Mungo Baobab. In a move typical of his derring-do, Baobab followed the mysterious annual rainbow comet, a phenomenon that led him successfully through the Cloak of the Sith and near enough so that liberated prisoner Noop Yeldarb could guide him the remainder of the way. This became the Baobab Merchant Fleet-established Manda-Roon Merchant Route, a replacement for the near-suicidal, Twi'lek-charted Death Wind Corridor connected to Ryloth.
Ancestors of Roon's current inhabitants arrived on-planet near the end of the New Sith Wars, when the Brotherhood of Darkness made its headquarters there. During the prosperous years of the Old Republic, the world had a small but consistent trade with independent interests, importing necessary technologies and exporting flame jewels, Roon spice, and the occasional Roonstones. Some time between 42 and 32 BBY, Mahwi Lihnn took a bounty on Roon.
Roon remained withdrawn from the New Order until 15 years before the Battle of Yavin, when Koong, governor of the Tawntoom province, contacted Admiral Terrinald Screed. Together, the two officials formed a loose and informal alliance to locate the cache of precious Roonstones. One of these Roonstones, which fell into the hands of Mungo Baobab, contained the text of the the legendary poem, Dha Werda Verda, which chronicled an ancient Coruscanti battle between the Taung and the Zhell.
It was after Screed's interest in Roon that the planet finally began to become drawn into galactic affairs once more. A handful of Rebel groups managed to operate in the system, working with the natives of the Umboo province, a part of the planet known to have long opposed outside authority. It was through great efforts that Governor Koong tried again and again to subjugate this hardy people, but never to any avail. This was largely due to the efforts of Baobab, whose exploits on the world not only led to the discovery of the hidden Roonstone mines, but also to their subsequent destruction at the hands of the governor.
Largely thanks to its isolation, Roon remained untouched by the Yuuzhan Vong War.