Some time prior to the Battle of Endor, control of Arkanis sector and most of the planets within its borders had fallen to the Rebel Alliance. However Tatooine was still under Imperial control.
After long years of occupation and harassment, the population, aided in large part by the exposure of Emperor Palpatine's death at Endor by the Rebel Alliance.
During the battle, Dark Jedi Sariss, who had worked for the local Imperial Governor, Tour Aryon, for many years, now saw an opportunity to leave her menial job by "disappearing" in the upheaval and link up with her master, Inquisitor Jerec, elsewhere.
When the uprising erupted, Imperial Prefect Talmont attempted to escape Mos Eisley as soon as possible. While he was crossing the city to reach his shuttle in Docking Bay 87, Talmont and his escort of sandtroopers were attacked by the Mos Eisley Militia and by Swang's Swoopers. The Militia wanted to capture the Prefect to judge him for his crimes. The swoopers just wanted to kill as many Imperials and militiamen as possible.
The liberation of Tatooine, coupled with the death of notorious gangster Jabba the Hutt, opened Tatooine up to influence from more organized authorities like the New Republic. However, it also began a series of wars between local rival gangs who were attempting to capitalize on the loss of the gangster boss.