A year has passed since the Star Force returned to save the Earth but another danger now approaches from deep space. A gigantic White Comet hurtles toward our galaxy, obliterating everything in its path. But it is no ordinary comet—it is the deadly Comet Empire, conqueror of worlds... and Earth is the next target! Against orders, the Star Force blasts off to investigate, but even if they can get past the flagship Andromeda, they don't yet know the true nature of their new enemy! (Source: AniDB)

In the year 2199, Earth is a mere shell of its former glory after a vicious bombardment by the Gamilas Empire. The inhabitants have been forced underground to escape the irradiated surface, but the deadly radiation inches closer and closer to the retreating population. With only one year before complete and utter extermination, time is fast running out and hope is in short supply. So far, any attempt to escape or retaliate has been instantly annihilated by the alien empire—until an emergency transmission from the planet Iscandar in a neighboring galaxy offers a glimmer of hope to save the doomed planet. Covertly, Earth's Self Defense Force constructs a faster than light engine for a journey to Iscandar. Armed with new weapons and a determined crew of fearless navy men, the World War II era battleship Yamato is reborn as Space Battleship Yamato. She and her crew set out on a perilous journey across the stars to save their home and the entire human race. [Written by MAL Rewrite]

With many of its central personnel lost in the war, the Earth Federation Government is forced to rebuild, and Brian Midcrid, president of the Unified Colonies, takes the position of its president. During an emergency session of the Federation Diet, he publicly acknowledges the existence of extraterrestrials, and reveals the events of the L5 campaign to the masses in what will later come to be called the "Tokyo Declaration." He goes on to state that these aliens pose a serious threat to humanity. (Source: Crunchyroll)

In the distant future, humanity has explored beyond Earth and colonized both the inner and outer planets of the Solar System. In order to protect the colonies and maintain law and order in the solar system, the Earth Federation Government (EFG) was created. Soon, many settlers started to resent the EFG's and its sphere of influence, straining the relationship between the central government and the colonies. While a strained peace was being forged between Earth and the colonies, a race of non-human creatures known as Deathcula invaded the System. Without provocation, they attacked the colonies and killed many of the colonists. The EFG quickly realized that the Deathcula were technologically superior and their forces were hopelessly matched. In order to have a chance at survival, Dr. Charles Louvre developed a transformable starship known as the Bismarck. Knowing that an advanced team of specialists were required to operate the Bismarck, four individuals came together and were charged with keeping the outer colonies safe from further Deathcula attacks. (Source: Wikipedia)