Much like several other movies and anime of its time Ginga Eiyu Densetsu (The Legend Of The Galactic Heroes) has its roots in WWII and pretty much compares the AXIS to the Allies.
Of course after a while it matters not because no matter how one tries to "like" the Alliance thanks to Reinhard Von Lohengramm and his righteous rule and all the "wrong doings" in the Alliance you can't help but to favor the Galactic Empire instead.
As others have pointed out although pretty much everything revolves around Reinhard the supporting cast is also part of the reason i've watched the entire series and movies at least twice. Of course in order to develop the characters sufficiently this anime spans to several movies and 110 episodes in total something which at least by todays standards is very rare (which is also why the 2018 version - Die Neue These - has compressed the first 20 episodes into 5).
Unfortunately i didn't like 2 things with this anime, first that the various formations in space are far from what could ever happen (sure it's space but logic applies i imagine even there) and 2nd that after everything Reinhard managed to accomplish in the end his life was taken by an desease which could not be cured.
Still one of the best anime ever released if you're into action/strategy ones (just be warned that you will be sad at some points more specifically when the two main support characters make their premature exit).
Review of Legend of the Galactic Heroes
