Coruscant provisional government

"In the month since the Battle of Jakku, the Empire has attempted no further large-scale offensives. Sources report all Imperial vessels within the Core and Inner Rim staying within the boundaries defined by the treaty. A few prominent members of the Provisional Senate have speculated that the New Republic's war with the remnants of the Empire has finally come to an end and that a final surrender may be imminent. However, in her address today, the chancellor warned that all planets should remain on high alert, and the New Republic Starfleet should be kept on a war footing for the foreseeable future."

- A news holo a month following the Battle of Jakku

In the aftermath of the Galactic Civil War, the Galactic Empire was officially dissolved and supplanted by a provisional government  in the year 5 ABY. Located on Coruscant, a core world and the former capital of the Empire, the provisional government was officially led by Grand Vizier Mas Amedda who acted as the head of goverment but however, Amedda's administration was powerless as it was placed under the supervision of Republic overseers sent by Mon Mothma who held the executive power; their purpose to confirm that Amedda remained little more than a figurehead. Although a few Imperial remnants continued to hold out in the months after the signing of the Galactic Concordance, opposing the Grand Vizier's decision to surrender the Empire, the provisional government was recognized by the New Republic as the successor government of the Empire.

Origins
"You&hellip;you're serious. You want me to surrender&hellip;the entire Galactic Empire?''" "That's right." "I don't&hellip;" "You don't have the power, do you?" "I&hellip;" "''So, get it back. And then bring a treaty to our door."

- Grand Vizier Mas Amedda and Senator Leia Organa, on Velusia

In 4 ABY, Emperor Sheev Palpatine was killed in the Battle of Endor. Without the Emperor, the Galactic Empire splintered into various political and military factions such as Governor Adelhard's domain in the Anoat sector. At the same time, the Rebel Alliance capitalized on its victory at the Battle of Endor, reforming into the New Republic while Imperial authority increasingly diminished across the galaxy.

Formation
Within a year of the Emperor's death, the Empire was decisively defeated by the New Republic at the Battle of Jakku, resulting in the death of the usurper and Counselor to the Empire Gallius Rax. Though a few Imperial remnants continued to persist in their resistance, the Galactic Civil War came to an end in 5 ABY. Following the dissolution of the Imperial government, a provisional government was established in its place under the leadership of Grand Vizier Mas Amedda, who escaped from Coruscant after Rax had him imprisoned in the Imperial Palace. Amedda represented the Empire at the signing of the peace treaty known as the Galactic Concordance on the former Republic capital planet of Chandrila, an event announced by the Republic to various sectors&mdash;such as the Velcar sector, where Governor Ecressys had already fled in advance to the Western Reaches with the wealth of hundred of worlds&mdash;across the galaxy.

The conditions of the Concordance required the former Empire to remain within the predetermined boundaries set in the Core Worlds and Inner Rim, reducing it to a rump state. It also prohibited the use of torture as well as the recruitment and mobilization of stormtroopers, reducing the Empire's once-vast military through severe disarmament treaties and war reparations. In addition, the Empire had to shut down the Imperial Academy system; and although they ceded control of Coruscant to the Republic, the provisional government was permitted to remain on the former Imperial capital. Over time, political hardliners rose to dominate the internal affairs of the post-war government.

Non-combatant functionaries were pardoned by the Republic and allowed to remain part of the provisional government, but on the condition that they adhere to the terms of the treaty. As such, Republic observers were tasked with monitoring Amedda's government while the New Republic itself concentrated on restoring the rule of democracy. Others fled into hiding after all surviving Imperial officials were categorized as war criminals by declaration of Chancellor Mon Mothma of the New Republic. Among the officers who eluded capture by the Republic was Nash Windrider, a commander who withdrew to the Queluhan Nebula along with remnants of the Imperial Navy. Despite its size, the fleet was able to hide its presence from Republic sensors by using the nebula's ionized gases for cover. Other Imperial officers and loyalists&mdash;such as Rae Sloane, Commandant Brendol Hux, and his son Armitage &mdash;along with nobles, technologists, and warlords embarked on an exodus into the Unknown Regions of the galaxy where they would ultimately establish a military junta known as the First Order.

Politics
The provisional government of Coruscant was a powerless regime led by a nominal leader; the grand vizier of the former Galactic Empire, Mas Amedda retained his position for his part in ending the Galactic Civil War. By design of the New Republic, however, he would only serve as a figurehead as the real power would be held by overseers from the Republic. Coruscant was in a state of turmoil at the time of the provisional government's formation, having experienced a decline in public order and the planetary civil war that followed in the wake of Emperor Palpatine's death.

Behind the scenes
Mas Amedda's provisional government was first mentioned in Chapter 38 of the canon novel Aftermath: Empire's End, which was written by Chuck Wendig and released on February 21, 2017.

Appearances

 * Aftermath: Empire's End