Ninth Battle of Iserlohn
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The Ninth Battle of Iserlohn (Japanese: 第9次イゼルローン攻防戦) was the Galactic Empire's attempt to retake Iserlohn Fortress from the Free Planets Alliance, with an Imperial fleet under High Admiral Oskar von Reuenthal against the Iserlohn Garrison Fleet under Admiral Yang Wen-li. The engagement was part of the larger Operation Ragnarök and was ultimately served the purpose of a distraction for the Alliance while the bulk of the Imperial navy seized control of Fezzan, as the first stage to an invasion of the Alliance through the Fezzan Corridor.
On 20 November 798 UC (489 IC / 3598 CE), in accordance with the planned Operation Ragnarök, Imperial High Admiral Oskar von Reuenthal, along with Admirals Helmut Lennenkampf and Cornelius Lutz, led a fleet of 36,000 warships against Iserlohn Fortress. It was a diversionary measure as the bulk of the Imperial Fleet was actually going to enter the Fezzan Corridor, annex the Dominion of Fezzan, and proceed to invade the Free Planets Alliance from there.