The Galactic Concordance was a historic peace treaty that marked the end of the Galactic Civil War, a power struggle between the Galactic Empire and the Alliance to Restore the Republic, and in–turn the New Republic. The treaty was signed by Grand Vizier Mas Amedda and Chancellor of the New Republic Mon Mothma on Chandrila after the final defeat of the Empire on Jakku. It formalized the Empire's surrender and dissolution a year after Emperor Sheev Palpatine's death during the Battle of Endor.
Decades after the Empire's fall, the First Order had begun to emerge from the Unknown Regions and became locked in a Cold War with the New Republic. The defiant First Order violated the treaty agreed by the Old Empire and began efforts to reclaim the lost legacy.
The Galactic Concordance officially ended hostilities between the New Republic and Galactic Empire, and stipulated that the Empire remain within predetermined boundaries in the Core, Colonies, and Inner Rim and cease large-scale offensives following its surrender. It also called for the end of the recruitment and mobilization of stormtrooper forces, the abandonment of the numerous Imperial Academies scattered across the galaxy, and the ultimate end to the Galactic Civil War. It also called for the Empire to give up its claim on the Core World of Coruscant to the New Republic, as well as imposing strict disarmament treaties and punishing reparations on the Empire. The Galactic Concordance prohibited galactic corporations from working with the remnants of the Empire, though corporations would work around this. In response, BlasTech Industries and Merr-Sonn Munitions, Inc. created the subsidy called the Sonn-Blas Corporation which operated within First Order space. As part of the treaty, the New Republic plegded to disarm itself, which it achieved via the Military Disarmament Act.
With the dissolution of the Galactic Republic in 19 BBY, Supreme Chancellor Sheev Palpatine issued the proclamation of the New Order, effectively wiping away the thousand-year-old Republic in an instant and replacing it with his own Galactic Empire, placing himself as its first Emperor. Having eliminated the Republic and the Jedi Order through betrayal from within the Grand Army of the Republic, Palpatine would oversee the ruthless expansion of his Empire and the genocidal actions of his regime, ultimately hoping to control the galaxy and supplant all galactic authority with his new restored Sith Empire.
Eventually, a loose coalition of rebel cells would come into existence to question his rule, while the eventual Alliance to Restore the Republic would be formed shortly before the destruction of the Empire's First Death Star. With the growing resistance movement threatening to end his reign, the Emperor embarked on a massive military effort to crush the Rebellion and its leaders, branding them terrorists and traitors to his rule. The following five years of galactic conflict known as the Galactic Civil War would see numerous attempts to finally crush the Rebellion, with most ending in failure. Following Operation Ringbreaker and Yellow Moon, the Alliance would launch a successful attack against the Emperor's second Death Star under construction over the Sanctuary Moon of Endor.
Following the destruction of the Empire's new battle station, along with the death of Emperor Palpatine and his right-hand man Darth Vader, the Rebel Alliance's successor government the New Republic would slowly push its way towards the Empire's capital of Coruscant in an effort to restore freedom to the galaxy. The New Republic re-established the Galactic Senate on Chandrila. Over the next year, the New Republic would win a string of victories against the Empire, and liberated numerous worlds including Akiva, Sevarcos, Kuat, Arkanis, and Kashyyyk from Imperial rule.
The Empire splintered into different factions including Lozen Tolruck's Kashyyyk remnant, Governor Ubrik Adelhard's Imperial remnant, Governor Ecressys' Imperial remnant, and Grand General Kenner Loring's faction. The Imperial Navy was commanded by Grand Admiral Rae Sloane's forces in the Vulpinus Nebula. While the public face of the Empire, Sloane was a puppet of Fleet Admiral Gallius Rax, who secretly controlled other Imperial forces in the Almagest, the Recluse's Nebula, the Ro-Loo Triangle, and the Inamorata. Rax was also privy to the Emperor's secret Contingency, a plan to destroy the Empire should it outlive Emperor Palpatine.
After sending Sloane to negotiate faux peace talks with the New Republic, Rax engineered the Liberation Day attack on Chandrila. In Sloane's absence, Rax seized power as Counselor to the Empire and ordered the Imperial fleets to assemble at Jakku. While Rax publicly claimed that he wanted to prepare the Empire for a final showdown with the New Republic, his plan was to destroy both the Imperial and New Republic forces by detonating the planet's core. Several months later, Norra Wexley and her team discovered the Imperial forces on Jakku.
Following some deadlock in the Galactic Senate, Chancellor Mothma managed to secure sufficient votes to send New Republic forces to Jakku. After a fierce space and land battle, New Republic forces led by Admiral Ackbar managed to break the Imperial defenses by downing Rax's flagship, the Super Star Destroyer Ravager. Norra and Sloane then joined forces to stop Rax from detonating Jakku's core. After Rax's death, Sloane fled into the Unknown Regions with Commandant Brendol Hux, his son Armitage, and a contingent of Rax's child soldiers aboard a replica of the Emperor's yacht Imperialis.
Amidst the fighting on Jakku, Grand Vizier Mas Amedda escaped from house arrest on Coruscant with the help of the Anklebiter Brigade, a group of child resistance fighters based on Coruscant. With the Imperial Navy destroyed, facing internal unrest, and a large amound of promising leader fleeing to form a remnant in the Unknown Regions, Amedda initiated contact with Chancellor Mon Mothma and sued for peace. The two leaders met on the crystal cliffs north of Chandrila's capital Hanna City. For the signing of the Imperial Instruments of Surrender, Mothma was accompanied by Princess Leia Organa, and her two new advisers: the former Imperial loyalty officer Sinjir Rath Velus and Hosnian Prime's Sondiv Sella. On the day that the Instruments of Surrender were signed, Leia went into labor and gave birth to her son, Ben Solo.
The Concordance, which had gone through a lengthy process of modification, agreement, and ratification, ordered the Empire to cease fighting and called for the final disbandment of Palpatine era government, forcing Amedda to step down as head of the Empire. Mothma also signed a further declaration classifying all surviving Imperial officers who did not adhere to the terms of surrender as war criminals. However, non-combatant functionaries including Amedda were granted conditional pardons. Under the terms of surrender, the Imperial remnant was also compelled to accede to the demands of the Galactic Concordance, including a ban on the recruitment and mobilization of stormtroopers, the abandonment of the galactic-wide network of Imperial Academies, the surrender of Coruscant to the New Republic, and the confinement of the remaining Imperial Navy to predetermined boundaries in the Core, Colonies, and Inner Rim.
Despite the Imperial surrender, Imperial holdouts on Jakku and elsewhere continued resisting the New Republic for several months. New Republic forces eventually overcame the remaining Imperial forces on Jakku. As a result, the New Republic Defense Fleet remained on war footing in the months after the Battle of Jakku. Many Imperial warships also fled to the Unknown Regions.
Some remaining Imperials refused to adhere to the terms of surrender as was done in the Core Worlds. These Imperial hardliners organized themselves into a separate remnant. While the conflict was never officially reignited, a Cold War broke out between those factions. Later, these holdouts would to relocate to the Unknown Regions, including Grand Moff Randd's Queluhan Nebula remnant.
In the wake of the treaty a massive amount of Imperial territory was absorbed into the New Republic. The treaty's advent led to a push for peace and demilitarization by the Republic, which feared repeating the mistakes of the former Galactic Republic during the Clone Wars. One of the first acts of the restored Galactic Senate was to pass the Military Disarmament Act, which reduced the New Republic Defense Fleet and armed forces to a token force compared to what the galaxy had as part of the Galactic Empire. Despite this, the Republic would still maintain the largest fleet in the galaxy; nevertheless, it was a fraction of the size of the Republic Navy at the height of the Clone Wars.
With the Senate now firmly believing the Imperial remnants posed little threat, it turned its attention to reshaping galactic politics, most notably deciding not to place its new capital on Coruscant but rather have its capital shift across member worlds by a process of election. This moving rotation convinced many of the Republic's intentions of not becoming another Galactic Empire, and increased its membership to include many dissatisfied systems that had withdrawn from the Old Republic and formed the Confederacy of Independent Systems during the Secessionist Movement.
Despite the Empire's collapse, Imperial loyalists formed the secret Shadow Council that consisted of remnant warlords in hopes of restoring the Empire to its former glory and awaited Grand Admiral Thrawn's return and the re-emergence of the former Imperial Military.
By 34 ABY, Chancellor Lanever Villecham and the rest of the Galactic Senate focused primarily on forging improved trade relations with the neutral systems of the Trans-Hydian Borderlands, despite the growing threat of the isolationist First Order, who disagreed with the outcome of the war.
While the Chancellor believed the First Order posed no threat as long as it adhered to the dictates of the Galactic Concordance, the First Order had in reality been skirting the stipulations of the treaty. The First Order was utilizing new Resurgent-class Star Destroyer, which were in themselves a clear violation of treaties governing capital ships, along with blatantly ignoring New Republic bans on the Order's purchase of weaponry. In a further attempt to undermine the legitimacy of the Galactic Concordance, the First Order began the massive mobilization of stormtrooper forces and expansion of its Army and Navy, along with training its new personnel on ship-based Academies, causing many First Order personnel to view these new vessels as their homes. The First Order also developed a new generation of IT-000 interrogator droids, thus violating New Republic laws banning torture.
Despite this, many in the Senate believed the rumored reports of growing First Order strength to be needless warmongering and alarmist speech. Individuals such as Leia Organa voiced some of the strongest protest over the First Order's mobilization for war, but corruption and ignorance branded her for fear mongering, along with tarnishing her image and reducing her reputation. Believing that the Republic was not doing enough to secure the safety of its citizens, General Leia Organa led her private military force known as the Resistance—which was funded from like-minded senators who shared her fears over the First Order—in an attempt to keep the Order in check. Despite not being sanctioned by the New Republic, the Resistance was unofficially supported by the Senate, which was hoping to avoid a conflict against the Imperial successor.
The Galactic Concordance was introduced in the 2015 reference book Star Wars: The Force Awakens: The Visual Dictionary, written by Lucasfilm Story Group member Pablo Hidalgo, though it mistakenly states that it was signed on Coruscant.
The Star Wars Legends version of the end to the Galactic Civil War was the Pellaeon–Gavrisom Treaty, which was signed nineteen years after the Battle of Yavin between the New Republic and the Imperial Remnant. In the Legends continuity, the Remnant and the Republic took longer to reignite the war, having settled their differences and eventually joined together as one. It would be more than a century after their first peace, when the Galactic Alliance was destroyed by the Empire and their shadowy "benefactors".