Hosnian Cataclysm

"Today is the end of the Republic! The end of a regime that acquiesces to disorder! At this very moment, in a system far from here the New Republic lies to the galaxy while secretly supporting the treachery of the loathsome Resistance. This fierce machine which you have built, upon which we stand, will bring an end to the Senate! To their cherished fleet! All remaining systems will bow to the First Order! And will remember this... as the last day of the Republic!"

- General Armitage Hux

The Hosnian Cataclysm, also known as the destruction of Hosnian Prime or the destruction of the Hosnian system, was the destruction of the Hosnian system at the hands of the First Order in 34 ABY&mdash;thirty years after the Battle of Endor. The event took place during the cold war and marked the annihilation of Courtsilius, Raysho, Hosnian, Cardota, and Hosnian Prime, the capital of the New Republic. Its destruction was carried out by Starkiller Base, a superweapon capable of destroying entire star systems. With the destruction of Hosnian Prime came the destruction of the Galactic Senate and the home fleet of the New Republic Defense Fleet. The massive sub-hyperspace ripple created by the destruction of the system caused the event to be visible in real time around the galaxy, including the planets of Takodana and Vardos. When the First Order did it, the conflict between the First Order and the Resistance escalated into full open warfare.

In the aftermath of the event, General Leia Organa of the Resistance organized a counterattack to destroy the First Order superweapon. The Battle of Starkiller Base ensued, resulting in the base's destruction moments before Starkiller was ready to fire on D'Qar, the location of the Resistance base. However, the extermination of the Galactic Senate and a large part of the Republic fleet, as well as the massive loss of life, left both the New Republic and the Resistance in a vulnerable position while the armed forces of the First Order moved to take control of the galaxy.

Prelude
"The weapon. It is ready. I believe the time has come to use it. We shall destroy the government that supports the Resistance, the Republic. Without their friends to protect them, the Resistance will be vulnerable, and we will stop them before they reach Skywalker." "Go. Oversee preparations." "Yes, Supreme Leader."

- General Hux, and Supreme Leader Snoke

At the end of the Galactic Civil War, the Galactic Empire was left defeated by the New Republic, the government formed by the Alliance to Restore the Republic after the death of the Emperor during the Battle of Endor. The Empire officially signed a treaty, the Galactic Concordance, with the Republic, keeping the remnants of the Imperial confined to their territories in the Core Worlds and the Inner Rim. What remained of the Imperial Starfleet, however, retreated into the Unknown Regions and ultimately formed the First Order, a successor force with the goal of destroying the New Republic and bringing order to the galaxy. As part of their plan, the First Order built a fleet in the shadows of the Unknown Regions and constructed a new superweapon called Starkiller Base, one capable of destroying entire star systems. The construction of the Starkiller weapon marked the culmination of efforts by the Old Empire to research dark energy translations and hyperspace tunneling, and it was a successor to the Death Star and the Death Star II superweapons that came before it.

During the conflict that had only just begun to spark between the First Order and the Resistance, Supreme Leader Snoke, the leader of the First Order, considered Luke Skywalker to be an existential threat to the designs of the First Order. Snoke believed that if Skywalker, the last of the Jedi, returned from the exile he imposed on himself after the destruction of his new generation of Jedi and aided the Resistance, a new Jedi Order could arise to threaten him. Kylo Ren, apprentice to Supreme Leader Snoke, attempted to find the last piece of a map that they needed to locate Skywalker, but his efforts at first proved unsuccessful. General Armitage Hux, commander of the Starkiller, argued in favor of using the weapon to destroy the Republic and eliminate the government he believed was illegitimate and ill-equipped to lead the galaxy. Hux argued that without the Republic, the Resistance would no longer be a threat. Snoke agreed and gave his permission to fire the weapon.

The Hosnian Cataclysm
"It was the Republic. The First Order, they've done it."

- Finn

On Snoke's command, Hux prepared the Starkiller weapon to be fired against the Hosnian system in the Core Worlds, the capital of the New Republic. When the weapon was ready, Hux addressed the legions of stormtroopers under his command who assembled to witness the destructive firepower of the weapon. Hux promised that this day would be the end of the New Republic and ultimately, the Resistance, the culmination of everything the troops had worked towards. Hux then commanded that the weapon be fired, and massive beams of energy were fired across the galaxy towards the Hosnian system. When they arrived, the astronomical bodies of the system were destroyed, including Hosnian Prime. With the destruction of Hosnian Prime, the capital planet of the Republic, came the destruction of the Galactic Senate and the home fleet of the New Republic Defense Fleet. The casualties on Hosnian Prime included Chancellor Lanever Villecham and Korr Sella, an envoy from the Resistance sent by General Leia Organa to warn the Senate about the threat of the First Order&mdash;a warning that came too late.

The firing of the Starkiller weapon released sufficient energy to create a temporary rip in sub-hyperspace. This caused the destruction of the Hosnian system to become visible from across the galaxy, causing terror and shock on countless worlds who had no idea of what was happening. The famed smugglers Han Solo and Chewbacca, along with stormtrooper defector Finn, witnessed the system's destruction from Takodana, in the Inner Rim. The sight led to confusion on Takodana, but Finn told Solo and Chewbacca that what they were seeing was the First Order using the Starkiller to destroy the Republic capital. Ex-Imperial and member of Inferno Squad Iden Versio also witnessed it from her home planet of Vardos. Resistance member Shriv Suurgav, who was also present, immediately knew that it was the First Order but was unable to work out what they had done until they were captured by First Order officer Gideon Hask; while Shriv was staggered and horrified, Hask referred to the system's destruction as a thing of beauty.

Aftermath
"The fuel cells have ruptured. The collapse of the planet has begun." "Leave the base at once and come to me with Kylo Ren. It is time to complete his training."

- General Hux, and Supreme Leader Snoke

After the destruction of the Hosnian system, the war raged on The Resistance mounted a reconnaissance run on Starkiller Base to learn more about the First Order base that destroyed the Republic. Tracing the route of the phantom energy beam, the Resistance identified the Starkiller's location and General Leia Organa ordered Black Squadron to develop a way to launch a reconnaissance mission on the base.

Jessika Pava designed a minimal stealth recon pod that would be towed into the Starkiller Base system by a T-70 X-wing starfighter, passively skim above the base's atmosphere while taking measurements, and then be picked up again by the X-wing. While Pava planned to pilot the pod, Temmin Wexley volunteered with his wife Karé Kun piloting the X-wing. The two had just been married and wished to spend as much time together as possible in the event that the Resistance was wiped out shortly thereafter.

The reconnaissance mission was a success, though Wexley was barely able to make it out of the atmosphere of Starkiller Base, sustaining damage and requiring him to broadcast the data to his wife, giving up his location to the First Order. However, she was able to recover his damaged pod by clamping it between the S-foils of her X-wing, bringing them back to D'Qar. However, due to this, the First Order was able to learn the location of the Resistance base.

With the location identified, the Resistance put a plan in motion to destroy the Starkiller before it could destroy D'Qar. Finn, Solo, and Chewbacca were sent to the weapon first to disable its shields, while Commander Poe Dameron led a starfighter assault against the base's thermal oscillator, which contained the energy that it drained from stars in order to power its weapon. The Resistance forces were able to successfully destroy the weapon but at the cost of a number of Resistance lives, including Solo and many starfighter pilots.

The Hosnian Cataclysm led to a complete shift in the galactic status quo. Although the New Republic had never had the size or influence of the Galactic Republic at its height, it had been the dominant galactic power since the Battle of Jakku. Now, with its political structure decimated and its important fleet in ruins, the First Order had established itself as the primary power in the galaxy, with resources sufficiently important to conquer it. Systems and planets across the galaxy, that had been tempted by the First Order's promises of security, instantly capitulated, while several others were taken by conquest. A few Senators had survived the destruction of the New Republic, as had several units of the military. However, the remaining taskforces had been dissolved by the Senators, who redirected the last forces of the Republic fleet to protect their homeworlds from the First Order.

In the Resistance's estimate, the First Order would seize the Core Worlds in a matter of weeks.

Behind the scenes
The destruction of the Hosnian system was depicted in the 2015 film Star Wars: Episode VII The Force Awakens. It was suggested by Pablo Hidalgo, creative executive of the Lucasfilm Story Group, that the reason the blast from Starkiller Base could be immediately seen from Takodana was due to a "sub-hyperspace rip side-effect" of the Starkiller.

Non-canon appearances

 * LEGO Star Wars: The Force Awakens
 * LEGO Star Wars: The Force Awakens