Representative of the standard battleship design of the Imperial forces of the Goldenbaum dynasty cira 750 Space Calendar, specifically during the second battle of Tiamat. Dagda was a formation leader in the Imperial fleet during the battle, and was caught in a crossfire and destroyed when the Free Planets Alliance forces successfully predicted their actions.
Essen was one of the battleships in the fleet that encountered the Free Planets Alliance forces in Space Year 640. Though Essen herself was destroyed, ships of her class persisted long afterwards. Given its age, most of these ships are in private fleets.
Essen is not canonically named in the animation. The only battleship named is the Gottingen, but I can't make out the Bablefish translation Xx;
The Rhine was one of the battleships to participate at Amlitzer within the fleet under Willibald Joachim von Merkatz. She remained with the Merkatz fleet, but during the flight of the nobles under Littenheim, the crew was torn between their loyalties. A mutiny occurred a third of the way into the voyage to Geisburg fortress and she came under the command of Pro-Lohengramm forces. She surrendered herself to the Metermeyer fleet, where she was recommissioned under the Lohengramm banner.
She remained with the Metermeyer fleet up until the end of the series, suffering damage while fighting with the Reuantal forces.
Rhine is a creation of my own, not emphasized in the series.
Not entirely happy with the way it came out. I might revisit it later.