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The Westerland Massacre (Japanese: ヴェスターラントの虐殺) was a critical turning point in the Imperial Civil War. The planet Westerland was part of the territory held by Duke Otho von Braunschweig. In the aftermath of military setbacks, the Lippstadt League began heavier resource extraction from the territories under its control in order to prepare for an anticipated siege of their main base, Geiersburg Fortress. On Westerland, the commoners rose up in revolt and Duke Braunschweig's nephew, Baron Scheidt, was killed. (LOGH: 'The Fall of Goldenbaum')
Enraged by the death of his relative at the hands of commoners, Duke Braunschweig decided to make an example of the entire planet by launching nuclear missiles at it. The use of nuclear weapons on inhabited worlds had been a taboo since the Thirteen Day War. He overruled his aide, Commodore Ansbach, who had advocated a more selective policy of punishing only the ringleaders of the rebellion. (LOGH: 'The Fall of Goldenbaum')
The news of the impending attack quickly came to the attention of Reinhard von Lohengramm's forces. Lohengramm's first impulse was to send forces to stop the attack at once. This decision was opposed by Paul von Oberstein, Lohengramm's adjutant at the time. Seeing a chance to quickly bring the Imperial public squarely against Braunschweig's group and, by this, hasten the end of the conflict, Oberstein argued to let the assault happen and use it as a propaganda device. Although initially horrified by the very idea, the lure of a shortened conflict was strong enough that Lohengramm was torn between the very different moral choice and pratical choice set before him. Indecisive, he suspended deciding until the timetable made that decision unavoidable.
Oberstein, however, had deliberately lied to Lohengramm about the time of the attack, which occurred ahead of the time that Oberstein had stated. Oberstein had also sent ships to spy on Westerland and record the attack.
Approximately two million people were killed in the attack. Images of the lifeless wasteland that Westerland had been reduced to were broadcast to populations around the Empire. This decisively swung public opinion against the Lippstadt League, and devastated the morale of its troops. Massed desertions followed and some nobles committed suicide. The cause of the high nobles had lost all legitimacy and the subsequent swift surrender of Geiersburg Fortress's garrison was in part due to the seeds of insurrection sown by the Westerland Massacre. (LOGH: 'The Fall of Goldenbaum', 'Roses at Summer's End')
The Westerland Massacre remained an unforgivable act of genocide throughout later history, but its immediate effects were to solidify the military and civilian elements of the Empire around Lohengramm, who would later use this to craft the Goldenlöwe Dynasty and the New Galactic Empire.
Not all of its effects were good for Lohengramm's side, however. Rumours remained that Lohengramm might have stopped the attack but was dissuaded from that path by Oberstein. When learning this, Siegfried Kircheis, by then the most powerful of Lohengramm's admirals and his sole true friend, denounced the tactic, creating a major rift between the two men that was never resolved before Kircheis's untimely death.
It also had the effect of tainting Oberstein in the eyes of the other admirals, who found the man's efficient and ruthless utilitarian tactics distasteful.
Oberstein would later state that the massacre hastened the end of the war by at least three months, and saved no fewer than ten million lives. For his part, despite thinking that the massacre might have well been a necessary evil, Lohengramm never fully reconciled himself with having hesitated in stopping the attack, thus indirectly causing it to happen. It would remain one of his most haunting regrets. (LOGH: 'Roses at Summer's End')