Bespin was an immense gas giant located in the vicinity of the Anoat system, a desolate sector of the galaxy. Bespin had several moons, and its gaseous mass contained a thin stratum of habitable atmosphere. Its layers were a source of rare Tibanna gas, which was harvested and refined in several mining complexes, including Cloud City, an opulent metropolis suspended in the planet's huge billowing clouds. The Ugnaught city of Ugnorgrad also was located over the planet, being ruled by King Ozz in the time after the Battle of Endor. During the Galactic Civil War, Bespin remained unaffiliated, but that did not prevent the Galactic Empire from garrisoning the planet and seizing Cloud City. However, with the Empire's defeat at Endor, the gas giant and its prosperous mining colony ended up recovering their freedom.
Swimming pools were considered a rare luxury on Bespin.
The planet Bespin was a gas giant that was about 118,000 kilometers in diameter. Like most gas giants, it had a solid core made of metal (in this case, rethin, 6,000 kilometers in diameter) followed by layers of metallic gases. Most of the layers of gas were poisonous, and the pressure and temperature were far above what a Human could tolerate. Despite this, from approximately 150 to 180 kilometers down from space there was a 30 kilometer thick habitable layer known as the Bespin Life Zone. This layer had an oxygen atmosphere with temperature and pressure suitable for Human life. It was in this layer that Cloud City was located. As with many gas giants, Bespin had a number of moons. Bespin had a twelve-hour day, and completed a revolution around its star approximately once every fourteen years.
Bespin's fauna included the winged Tibannucks, velkers, rawwks, the gas-filled beldon, and airborne algae sacks. Bespin was the type class of the Bespin-class gas giant.
Old Republic Era
The planet was first discovered by the explorers from the Hyperspace Navigator's Guild in years prior to the Mandalorian Wars. The carbonite-rich Empress Teta established a small gas operation on the planet, but it was mostly destroyed during the Mandalorian Wars by a fleet of Mandalorian warships, hoping to break up the tibanna gas supply chain for the Galactic Republic.
Bespin was first colonized in 1989 BBY. The planet had its own Jedi Enclave. During the New Sith Wars, the Brotherhood of Darkness captured the planet. Lord Ecclessis Figg commissioned Cloud City to be built by the Incom Corporation around 400 BBY.
Rise of the Empire Era
In 22 BBY, the planet served as a refuge for children orphaned by the Clone Wars. During the Dark Reaper Crisis, the planet fell to the Confederacy of Independent Systems. Later on the planet was a site of several small battles between the Galactic Republic and the CIS, in which the Republic ultimately managed to regain and keep control of the planet. After the Republic was reorganized into the Galactic Empire, the planet was placed under Imperial control, although it was largely left alone beyond that.
This was the planet on which Galen Marek found Rahm Kota when he was searching for potential leaders of the Rebel Alliance. The former Jedi had hidden himself on one of Bespin's many construction platforms and Marek fought one of the Emperor's Shadow Guard during the meeting. Marek also rescued Senator Garm Bel Iblis while Cloud City was filled with criminals and thugs.
Galactic Civil War
During the Galactic Civil War, Lando Calrissian served as Baron Administrator of Cloud City. He helped provide well-paying jobs for the Ugnaughts, and was admired and liked by the citizens of Cloud City.
When Han Solo, along with Leia Organa, C-3PO, and Chewbacca came to Cloud City in 3 ABY to escape from the Empire, they walked into a trap set up by Darth Vader, which Lando was forced into aiding. Han Solo was frozen into Carbonite and Leia Organa and Chewbacca were to remain in the city. As Boba Fett brought Han onto his ship, Slave I, Lando with Lobot's help, got the two out of Imperial controller along with blasted Threepio and tried to rescue Han from Fett but failed.
Meanwhile, Luke Skywalker dueled Vader, lost his right hand, and Vader revealed that he was Luke's father. Pinned between the choice of going with his long-lost father or dying by his blade, Luke plunged into an air vent. When he fell, he managed to grasp onto a weather vane beneath the city. In pain from his wound and his new knowledge, Luke pleaded for Obi-Wan Kenobi's help, to no avail. He managed to telepathically communicate with Leia, and was rescued by the Millennium Falcon. The Falcon in turn managed to escape from the Executor when R2-D2 fixed the disabled hyperdrive.
However, a garrison of troops was left on the planet, and the garrison fought against the Rebel Alliance and Bespin security forces for control of Cloud City's Gravity Control Generators. The garrison also destroyed the Bespin Government Center and built an Imperial Palace in its place to cement their occupation. Calrissian's former assistant, Lobot, temporarily ousted the garrison from the planet by tricking them into thinking Cloud City's repulsorlift pods were compromised.
Later, just before the Battle of Endor in 4 ABY, the Alliance raided the still Imperial-controlled colony with the help of Rogue Squadron. The successful raid secured shipment of vital tibanna to the Rebel cause. The main battle to free Bespin was fought right after Endor. Calrissian, now a general in the Rebel Alliance, led the Rebel SpecForces against the Empire and successfully ousted the occupying troops. The Jedi X2 was also involved in liberating the city with the help of Calrissian and Lobot. Calrissian himself would eventually return to being Baron Administrator.