The destruction of Jedha City, also referred to as the destruction of the holy city, or as the massacre at Jedha, occurred during the reign of the Galactic Empire when the Empire, in an effort to test the superlaser of the Death Star, used the battle station to destroy the holy city of the moon Jedha. Operating on a single reactor for the superlaser's power, the Empire evacuated the Imperial occupation force before moving the Death Star into orbit, targeting the holy city, and destroying it. The blast caused not only an enormous explosion but also significant damage to the moon, throwing fire, smoke, and dirt into the upper reaches of the atmosphere. On the ground, the shockwave caused Jedha's surface to begin peeling back, destroying everything that it touched. The Empire subsequently fabricated a cover story for the Imperial Senate that Jedha was destroyed in a mining disaster.
By the time of the Cold War, some dismissed the destruction of the city as mere Imperial propaganda capitalizing on the "actual" mining accident.
As the Galactic Empire completed the Death Star, one of its scientists, Galen Erso convinced Imperial cargo pilot Bodhi Rook to defect and take a message to Saw Gerrera and his partisans on Jedha. Rook returned to his homeworld of Jedha. There, he surrendered to the partisans and was taken right to Gerrera. During this time, Rebel Alliance Intelligence officer, Captain Cassian Andor learned of the message from Tivik on the Ring of Kafrene.
Grand Moff Wilhuff Tarkin and Imperial Military Department of Advanced Weapons Research Director Orson Krennic watched the Death Star's completion aboard the Executrix. Tarkin learned that Krennic had a defector loose in Jedha City and was decided to test the weapon to prevent more systems from joining the Alliance. The Alliance sent Captain Andor, K-2SO and Professor Erso's daughter, Jyn Erso to verify the pilot's claim and find Professor Erso. Andor, Erso, Chirrut Îmwe, and Baze Malbus were captured by the partisans and taken to the Catacombs of Cadera. There, Gerrera gave Jyn the message from her father.
The Holy City's destruction seen from the Catacombs of Cadera
Despite Krennic wishing to destroy Jedha in its entirety, Tarkin decided that they did not require a pronouncement of the Death Star's power, and chose to destroy Jedha City only. He also ensured that Lord Vader and the Emperor would not be there in case of any embarrassment. After Protocol 13 evacuated all Imperial forces from the city, Krennic gave the order and destroyed the city. The city was destroyed in a matter of seconds and the shockwave moved the catacombs. Some of the partisans, except Gerrera made their escape. In his last moment alive, Gerrera simply said "Steela," the name of his sister, who had died during the Clone Wars. Andor, Erso, Îmwe, Malbus, and Rook were able to make their escape and meet up with K2 aboard the LMTR-20 U-wing before the shockwave destroyed the Catacombs.
Jyn Erso and her allies were able to escape the destruction unleashed by the Death Star via the U-wing LMTR-20.
Pleased with the test, Tarkin apologized to Krennic and decided to take command of the Death Star. Despite Krennic's objections, Tarkin told him that he needed to find and eliminate the defector's contact at the kyber refinery on Eadu. Andor and his friends continued with their mission and went to Eadu to rescue Professor Erso. In truth, Andor was under orders to eliminate Erso. Krennic arrived and demanded to know who supplied Rook with information on the Death Star. Professor Erso revealed himself as the traitor, but Krennic killed the other scientists.
The Alliance sent in Blue Squadron to bomb the facility. Erso was mortally wounded in the attack, but was comforted by his daughter before she, Andor, and their friends could escape. Lord Vader learned of Jedha City's destruction and the Alliance's attack on Eadu. He summoned Director Krennic to his Fortress on Mustafar to explain the problems concerning the Death Star. Vader told Krennic that there was no Death Star and that the Imperial Senate was told that Jedha City was destroyed in a "mining accident". Vader told Krennic to make sure that Erso did not compromise the weapon.
The ruins of Jedha
Jedha was reduced to a horrible state after the Death Star fired upon it despite the battle station only using a minor blast. While the Death Star would be destroyed in the Battle of Yavin, Jedha was left in decay. Surviving Partisans under Benthic continued the fight against the Empire on Jedha and intended to continue on elsewhere after the "death" of the moon. Imperial forces arrived to recover whatever kyber crystals were left on Jedha, only to be countered by the Partisans and several members of the Alliance proper in the battle for Jedha. After taking part in the mission to Shu-Torun, Benthic resolved to change and decided to bring the Partisans to Salobea instead of returning to Jedha.
The destruction of Jedha City was depicted in the 2016 Anthology film Rogue One: A Star Wars Story. The first footage of the event was shown in the first Rogue One trailer on August 11, 2016.
In Star Wars Legends, the event where the Death Star tested its superweapon was identified as the Destruction of Despayre.