A republic governed by a Diktat took the place of the Corellian empire as the ruling political system on the planet of Corellia. This system persisted for over three centuries, until the administration of Diktat Daclif Gallamby crumbled during the time of the Galactic Civil War.
The Corellian republic was, in theory, a republic operating under a constitution. Although it began as a democracy, it gradually transformed into a corporatocracy. This corporatocracy was controlled by the boards of directors from Corellia's most influential corporations, such as Corellian Engineering Corporation, Corellia Mining Corporation and Gowix Computers. The elected head of state, known as the Diktat, officially served as Corellia's executive leader and the governor of the Corellian sector, in addition to being the commander-in-chief of the Corellian Armed Forces. However, the Diktat's actual authority depended on the corporate entities that managed the government. Some Diktats were merely figureheads on Corellia, while others actively governed the entire sector.
The center of government and administration was located in the Governmental Sector of Coronet City, which functioned as Corellia's capital. The Coronet Capitol housed the Diktat's office.
The Corellian republic was established by Berethron e Solo, the last king of Corellia. He dismantled the Corellian empire in 312 BBY to introduce a democratic system to the planet.
When the Declaration of a New Order occurred, marking the Galactic Republic's transformation into the Galactic Empire, Dupas Thomree held the position of Corellian Diktat. Thomree reached an agreement with Emperor Palpatine to maintain his regime and the Corellian sector's autonomy. As a result, the sector became an Imperial client state. Dupas Thomree agreed to support Imperial galactic policies, provide tax revenue to the Empire, and ensure that the Corellian shipyards continued to produce Imperial warships. While the Corellian sector remained officially independent and the Diktat preserved his government, he essentially became a puppet ruler with control only over Corellia's administration. The sector and its Corellian Defense Force were, in practice, placed under the control of the newly appointed Grand Moff of the Corellian sector. This situation led to significant protests from Corellia's independent-minded population against the Diktat. Over time, Diktat Dupas Thomree grew distant from the people and increased restrictions on their freedoms. With the Empire's full backing and protection, the Diktat transformed into an autocrat, acting without concern for the population's protests. Furthermore, the position of Diktat became a lifetime appointment, with each Diktat choosing their own successor.
When the Galactic Civil War broke out between the Galactic Empire and the Rebel Alliance, Diktat Dupas Thomree agreed to provide Corellian military forces to support the Empire. Dupas Thomree passed away shortly after and was succeeded by his chosen successor, Daclif Gallamby, who was largely unknown to the public. During Gallamby's reign, the Galactic Civil War intensified. As Corellian armed forces were repeatedly deployed to aid the Empire against the Rebellion, piracy surged in the Corellian sector, and the local economy began to decline. Following the Rebel victory at the Battle of Yavin, the Diktat and his government grew paranoid, fearing overthrow by the Rebellion or their own people. Consequently, the Corellian government implemented strict isolationist measures, restricting trade and traffic throughout the sector. These measures led to the collapse of the Corellian economy.
After the Emperor's death at the Battle of Endor in 4 ABY, the Galactic Empire began to fragment. Initially, the regime gained strength from the massive influx of Imperial officers and troops seeking refuge in the Corellian sector. However, without the Emperor's direct protection, the Diktat's government weakened. The resentful Corellian population protested with increasing intensity, and the regime gradually lost power to the Triad of Sacorria. In 7 ABY, the Diktat disbanded the respected Corellian Security Force and established the Public Safety Service, an Imperialistic security force and political police tasked with protecting the regime. By 13 ABY, the Diktat's regime had fallen apart. As the population revolted, the Corellian armed forces and security forces ultimately ceased protecting the government. Daclif Gallamby and his supporters seized half the credits from the state treasury and fled the Corellian system. The Diktat's sudden disappearance led to the regime's collapse. The Corellian administration remained in chaos until the New Republic took control of the Corellian sector and appointed a Governor-General to govern Corellia and the sector.
In 18 ABY, during the Corellian Crisis, Corellian separatists from the Human League assassinated New Republic Governor-General Micamberlecto and seized control of Corellia. Their leader, Thrackan Sal-Solo, declared himself the new Diktat of Corellia, aiming to restore the previous regime. However, Sal-Solo's reign was brief, as the New Republic regained control over the Corellian system at the conclusion of the Corellian Crisis.
Approximately two decades later, following the end of the Yuuzhan Vong War, the New Republic eliminated the position of Governor-General of the Corellian sector. This allowed the Corellians to re-establish a democratic political system on Corellia, based on earlier Corellian institutions: the Five Worlds.