The Galactic Empire and the Free Planets Alliance have been locked in a seemingly endless war for more than a century and a half. In the Empire, a young Siegfried Kircheis meets Reinhard von Müsel and his older sister Annerose. Kircheis enjoys a happy friendship with the two beautiful blonde-haired siblings until the day that their alcoholic father, a lesser nobleman with low standing, accepts a request for Annerose to be sold as a concubine to the Kaiser. Although enraged, Reinhard is powerless to stop the whims of the Imperial Court. He and his father soon move away, leaving Kircheis behind.

A few years later, Reinhard returns in a military uniform and declares his intent to rise through the ranks and free his sister from sexual servitude. Kircheis joins Reinhard on this daring journey to save Annerose, yearning to forever stay by the side of his friends.

[Written by MAL Rewrite]

Led by Reinhard von Müsel, the Galactic Empire crushes the Free Planets Alliance in the Fourth Battle of Tiamat. Arriving in the Imperial capital of Odin to a hero's welcome, Reinhard's victory earns him a promotion to High Admiral and the distinguished title of Count von Lohengramm. On the other side, Yang Wen-li safely returns to the Alliance capital of Heinessen without fanfare and reunites with his dear friends.

Reinhard and Yang look forward to a long-awaited reprieve. However, at the request of the scheming Duke Otho von Braunschweig, the Imperial High Command orders the new High Admiral to invade the Alliance with a fleet of twenty thousand ships. After the Duke leaks the plan to the Alliance government, three fleets totalling forty thousand ships are sent to counter the incoming attack and recreate the famous Battle of Dagon. But even though Reinhard is outnumbered two to one, he has an ingenious plan—and Yang sees right through it. Will Yang's superiors heed his warning before it is too late?

[Written by MAL Rewrite]

In the year 2314 AD, the world is at peace. Thanks to the sacrifices of Celestial Being and its mobile suit pilots, the people of Earth experience a time of prosperity and unity, enjoying tranquil lives once thought impossible. Celestial Being, an organization once painted as villains by the Earth Sphere Federation, now exists in public perception as a group of heroes, celebrated in film and culture.

When an extraterrestrial threat arrives on Earth, threatening the newly acquired calm stasis, Celestial Being springs back into action. Led by ace pilot Setsuna F. Seiei, the Gundam Meisters of the group battle the hostile alien forces, teaming up with old rivals to protect the human race from certain doom.

[Written by MAL Rewrite]

At the climax of the Eve Wars, on December 24 of the year AC 195, the armies of the World Nation and White Fang met in a ferocious battle. World Nation leader Treize Khushrenada was slain, White Fang leader Zechs Merquise disappeared, and Earth was saved from destruction by the intervention of the five Gundam pilots. Having witnessed the consequences of war and hatred, the people of Earth and the space colonies put aside their differences and together founded a new world government. Under this newly-formed Earth Sphere Unified Nation, a year has passed in peace. The government and the populace have disarmed themselves, and almost every remaining mobile suit has been destroyed. Deciding to follow suit, Gundam pilots Heero Yuy, Duo Maxwell, Trowa Barton, and Quatre Raberba Winner place their mighty mobile suits inside an asteroid and send them on a one-way voyage into the sun. But even as they bid their Gundams farewell, a new conflict is drawing near. 

(Source: AniDB)