Derilyn had two main continents that made up the vast majority of the planet's land mass. The rest of the world was covered by vast oceans, save for ice caps at both poles.
The continents were both primarily made up of rolling plains, forests, and mountain ranges. The continent in the western hemisphere had a sizable desert.
The planet was settled by colonists from Elrood in 3000 BBY, joining the Galactic Republic. At some point in the Clone Wars, it was conquered by the Confederacy of Independent Systems.
Derilyn was subjugated by the Galactic Empire under Governor Afren Hul. It was the site of the Sixty Hour War between the Rebel Alliance and the Galactic Empire during the early part of the Galactic Civil War. During the invasion of the planet, six Imperial Star Destroyers annihilated the third largest city of Paran, using concentrated turbolaser fire. Several wings of TIE Fighters followed the assault to ensure the devastation of Paran was complete. The city was the home of Senator Wuxod, who was a vocal critic of Emperor Palpatine. Wuxod himself disappeared shortly before the invasion. Paran once had a population of over half a million people, though the population during the attack was reduced to about 3000. Most of the remainder died of injury, disease, and starvation.
Treidum made a run out to Derilyn of Roche Siak Protocol Droids but he was jumped by the Khuiumin Survivors.
In 1 ABY, the Rebel Alliance and the Khuiumin Survivors destroyed the Imperial-class Star Destroyer Brazen stationed at the Derilyn Space Defense Platform.
Derilyn was eventually liberated by the New Republic.
- Planets of the Galaxy, Volume Three
- The Star Wars Planets Collection
- The Jedi Academy Sourcebook
- Cynabar's Fantastic Technology: Droids
- Lords of the Expanse
- Gundark's Fantastic Technology: Personal Gear
- The Essential Atlas