The Confederacy of Independent Systems (24 BBY–19 BBY), abbreviated to CIS, and also known as the Separatist Alliance, the Separatist State, or simply the Separatists, was a secessionist government formed by thousands of star systems from the Mid Rim to the Outer Rim that broke away from the Galactic Republic. The Confederacy was founded on the grounds of excessive taxation and corruption within the Galactic Senate and general feeling of dissatisfaction towards and neglect by the Core Worlds, which contained some of the wealthiest and most prestigious planets in the galaxy.
The Confederacy was led by the former Jedi Count Dooku of Serenno, who served as its Head of State. In addition, the Confederacy was secretly supported by several corporations, including the Trade Federation, headed by Viceroy Nute Gunray; the InterGalactic Banking Clan, headed by Chairman San Hill; the Techno Union, headed by Foreman Wat Tambor; the Commerce Guild, headed by Presidente Shu Mai; the Corporate Alliance, headed by Magistrate Passel Argente; and the Retail Caucus.
The Separatist Crisis that began in 24 BBY led to a political crisis in which tensions escalated between the newly-formed Confederacy and the reigning Republic. In 22 BBY, the Confederacy and the Republic went to war using their respective military forces—the droid army and the Republic clone army—resulting in a pan-galactic conflict for the first time in a millennium.
The following three years saw the Clone Wars raging across the galaxy with the Separatists rapidly attempting to bring the Republic to its knees. Unknown to the majority of the galaxy, however, the war was merely a ploy—Supreme Chancellor Sheev Palpatine, the leader of the Republic, was a Sith Lord called Darth Sidious, who controlled the Separatists as Dooku’s Sith Master, and therefore influenced both sides in the war. By 19 BBY, the Confederacy suffered several major defeats in the Outer Rim Sieges as the end of the war approached, on top of losing a third of their fleet in the decisive and devastating Battle of Coruscant. After Dooku’s death, and Supreme Commander General Grievous‘s subsequent defeat on Utapau, the Separatist Council was executed on Mustafar. With the subsequent shutdown of the droid army, the Confederacy rapidly collapsed as the war came to an end. Following the end of hostilities, trade groups that had supported the cause were nationalized, and its remaining star systems reabsorbed into the Republic’s successor state, the Galactic Empire, ruled by Emperor Sheev Palpatine, while some elements of the droid army fragmented into several holdouts.