For decades, the Galactic Empire has been locked in an interstellar war with the Free Planets Alliance, a conflict that involves thousands of spaceships and millions of soldiers on both sides. Two new commanders enter the conflict with great hopes: Imperial Admiral Reinhard von Lohengramm and the FPA's Yang Wen-Li. As they deal with superiors and subordinates, maneuver through complicated political arrangements, plot strategies, and win battles, each will be tested, and ultimately, changed, by the reality of war.
(Source: Anime News Network)
— Description from AniList community (anilist.co).
