The planet Jabiim was subjugated during the Galactic Civil War as the climax of a prolonged conflict on Jabiim between the Galactic Empire and the local Jabiimi rebels, taking place in the decades after the Clone Wars ended.
Imperial forces invading Jabiim's surface.
Following the Clone Wars, Jabiim was subjugated and used by the Empire as a mining world, with the result of its valuable ore supplies being exhausted. During the Imperial occupation, a Jabiimite rebel group had been opposing the Imperials for about 19 years without support from other rebel groups.
They relied on stolen and obsolete Imperial equipment and rapid strikes to combat the Empire and their Jabiimi collaborators. Yet, Galactic Emperor Palpatine was not willing to pull the last of his stormtroopers off the planet. The harder the rebels fought, the tighter the Imperial grip became.
Potential help arrived in the form of the Rebel Alliance, which had hoped to convince the fiercely independent Jabiimi to join their galaxy-wide cause. They dispatched Luke Skywalker and several other Rebels to help the local rebels, though Skywalker didn't realize he stepped into his father's shadow—or that the name "Skywalker" could earn him a death sentence from his would-be allies. During the Clone Wars, as a Padawan serving the Galactic Republic, Anakin Skywalker had 'betrayed' the Jabiimi, and the locals did neither forget nor forgive.
Hobbie's X-wing under fire by Imperial forces above Jabiim.
Upon landing on Jabiim, they were greeted by a furious mob and were taken prisoner by the very people they had been sent to help. Luke tried to find out what exactly his father did many years ago. Meanwhile, the only people from whom they could expect any help—X-wing pilots Wedge Antilles and Derek Klivian—discovered an Imperial fleet approaching Jabiim with orders to kill or enslave its inhabitants. Among the Imperial fleet were Acclamator-class assault ships, being known for their use as slave ships. This told the two Rebel pilots that the Empire had come to enslave Jabiim.
Jabiimi's last stand, the Empire's final assault
On-planet, Luke Skywalker and his captors joined forces to repel an Imperial assault force of stormtroopers and immense walker transports like AT-AT and AT-TE walkers.
Luke had a hard time focusing his fledgling Jedi abilities, since he was haunted by the fact that his father, Anakin Skywalker, was not a hero to the people of Jabiim, but a traitor. After the disastrous Battle of Jabiim, Anakin had refused to evacuate the Jabiimi loyalists and as a result, the loyalists were subject to a Separatist rule of their homeworld.
With superior technology, the Imperials won the battle and crushed the rebellion. However, the Empire also made a deal with a group of wealthy Jabiimi: in exchange for their own freedom, they would give the rest of the planet's population to the Imperials as slaves.
What would complicate things further was the fact that Darth Vader himself was present in orbit above the planet. Haunted by the memories of his former life, he ordered a full-scale razing of the planet, destroying all life on its surface with the excuse that the Alliance would thus be deprived of a potential ally.
In the ensuing chaos, the rebel groups managed to escape and kill their Jabiimi captors, with the Jabiim rebels fleeing towards the nearest mines, now their only means of escaping the planetary bombardment.
Days later, the last mine-turned-fortress would fall to an Imperial ground force led by Lieutenant Janek Sunber. All remaining survivors were reportedly led to an awaiting slave-transport.
- The Complete Star Wars Encyclopedia, Vol. II, p. 131