Arene Massacre


 * "Even an ordinary human, if given a reason, can commit any level of wickedness. The evil done in Arene was that commonplace."
 * - The final report from Arene -

Arene Massacre was a destructive bombardment executed by Imperial Army during the Great War. It caused the city of Arene lost half its population. In Andrew's era, both nations were willing to have a joint memorial for it.

Background
As the Empire gradually advanced day by day, they finally retook the Lowland Industrial Area and pushed the front line to the Republic border. At that time, a massive trench war was ongoing on Western Front. Both belligerents were searching for a way to break the stalemate. The Imperial Arene-Roygen region, which had always been staunchly anti-Empire and contained sparks of partisan resistance. The city of Arene used to be a Republic city and was now a main point of the Imperial railway system that even had a switching yard. It had no alternative lines to replace it. As trains ran through there with tens of thousands of tons of ammunition and food per day, the city of Arene became an Achilles' heel of the Western Army Group.

The Republic
After failing to capture the Western Industry Area and withdrawing from Low Lands, the Republic Army successfully maintained their front line under the offensives of Imperial Western Army. Although the United Kingdom had below-the-surface contact with them, they feared to lose all their overseas interests as they accepted their assistance, trying to resolve things on their own to the extent as possible. Besides, the Imperial Army had struck into their territory, which also gave their supply lines the advantage. As the conclusion, the Republic was planing a major counterattack on Rhine Front. The Republic also made propaganda that contained the intent to dispatch a rescue to take the city of Arene back. Apparently, they were willing to pure oil on the fire if any incident occurred at a transport terminal of the Empire.

The Empire
The General Staff found it fundamentally impossible to frontally break through the enemy trench in west, suffering from heavy losses as well as the Republic. The Imperial light railway in west had reached its limit, and even a large-scale firepower offensive would put too much strain on supply lines. The burden on supply had blown through the prewar estimates of General Staff long ago. As the whole Great Army fought on Rhine Front, most of the Empire's forces were committed on here.

Aside from it, the Imperial Air Forces was basically out in full force every day and having trouble making up for losses in the Rhine Air Battle. The air units have more types of missions than expected. As a result, the plan created before the war starred meant absolutely nothing when it met the reality of borderline overworked air units being mobilized for missions they weren't expecting. It was only once the air units had been sent in that the military began to understand the necessity of the types of missions they could perform. Therefore, the Imperial Air Fleet lacked the forces to prevent a sneak attack in the rear.

On the other hand, as the war situation changed, the chances of combat in a city became extremely high. The law of war is extremely critical of involving noncombatants in urban battles. Supposedly, there was a trigger clause that allowed unlimited economic sanctions against countries that purposely attack in a way that involved noncombatants.

Hence, the General Staff tasked the Imperial War College with coming up with ways to handle urban warfare. Eventually, the war college adapted the plan assumed, from a purely military point of view, the situation that there are no noncombatant in the city, only enemy forces. In short, it would turn civilians into enemy forces by following a legal procedure to avoid the law of war. This plan was proposed after the idea was verified by looking at large-scale conflagrations of the past, and was proofed effective on army exercise grounds. Once the legalization was done, they would cause widespread fires via artillery bombardment from positions surrounding the city, causing the firestorm into the city at last.

Uprising
It started when a hunt for partisans turned into a military clash. Since Arene had always been staunchly anti-Empire, it didn't take a day for skirmishes to develop into a full-on uprising. The garrisons and military police failed to quash the sparks of rebellion, and the suppression unit the central General Staff promised had gotten held up. The situation got even worse when the Republic transport aircraft diverted the interception of Imperial Air Fleet and dropped the Republic mage 2nd company of special ops forces in Arene. Once there are mages guarding the city, it will need military intervention and heavy firepower weapons. If the Empire puts out the fire, the front lines will get trampled or break.

Suppression Plan
Upon receiving word that anti-Empire riots had broken out in Arene, Major General von Zettour proposed a swift, ruthless way to “cope.” Major General von Rudersdorf of the Operations Division immediately called an emergency meeting of the Imperial Army General Staff and got the operation approved as a joint proposal for the Service Corps and Operations. With it, the army had permission to send military forces into the city. Later, a multitude of reserve units were brought in by the trains, and 203rd Aerial Mage Battalion was supposed to be the vanguard. At 11 a.m. on the yesterday of X-day, Arene was given an evacuation warning. At 2:22 p.m. on X-day, the orders from the commander of Western Army Group were issued.

Operation
203rd Aerial Mage Battalion contacted the enemy mages first. After a short air battle, the Republic mages withdrew, shutting themselves up in the city. 203rd kept driving them off, and issued the warning to surrender to Arene.
 * "Release unaffiliated members of the general population immediately. We can't allow your slaughter to continue. We demand the release of imperial citizens according to article 26, paragraph 3 of the Rules of War on Land."

After the warning was issued, a small number of pro-Empire people attempted to escape and were shot in full view of the Imperial Army. In response, the Imperial Army started attacking the militia. The 203rd rescued the prisoners, and the artillery units bombarded the city. Most citizens in the city took refuge in and around Karelian Cathedral, which was famous as the white cathedral and later the place where the tragedy took part. As the prisoner rescue mission completed, the Imperial issued the last warning.
 * "This is a warning for the irregular combatants of the armed revolt. In accordance with artilce 8, paragraph 5, of the Rules of War on Land, I demand someone meet with our representative to discuss the subjects of the Empire you so unjustly imprison."

In response, the city of Arene said,
 * "We are the citizens of Arene. There are no prisoners. We are just people asking to be free."

According to the Rules of War on Land, since there were no prisoners and no imperial citizens among the irregular combatants occupying the city, the Empire carried out an operation to capture the city. 203rd eliminated the Republic mages, and the artillery units attacked targets that were likely to spread the flames as proof-of-concept for a firestorm. They used high explosives to smash the roofs of stone buildings. Once the flammable items inside were visible, they dropped incendiary bombs inside. To prevent the fires from going out, they used more high explosives to shatter the buildings, creating gusts of wind to help the conflagration spread. Then more incendiary bombs. That repetition finally set all of Arene ablaze in a few short hours.

Aftermath
Although the Empire safely suppressed the uprising without the destructive rout of Western Army Group, a notorious atrocity has been done by the Empire in history. Furthermore, the railway of the city of Arene had been destroyed. The General Staff had to make the prompt decision to their next step.

Trivia

 * Some Imperial bomber units also took part in the battle in novel and manga.
 * By modern wartime standards, The Republic Militia could be considered unlawful civilian combatants.

Reference
Plus Ultra - Chapter VI Ordeal of fire