From Gineipaedia, the Legend of Galactic Heroes wiki
In the summer of 791 UC (482 IC / 3591 CE), the cruiser Salerkrantz of the Merkatz Fleet was the first ship to come in contact with the damaged Imperial destroyer Hameln II, which was under temporary command of Reinhard von Lohengramm, after it escaped from an Alliance ambush. In December 794 UC (485 IC / 3594 CE) the Merkatz Fleet fought in the Sixth Battle of Iserlohn against the besieging Alliance forces. (MUT: 'Chapter IV', HBSHBL: 'A Hundred Billion Stars, One Ambition')
Merkatz and his fleet later fought under the overall command of then-High Admiral Lohengramm at the Battle of Astarte, in 796 UC (487 IC / 3596 CE), against the Alliance 4th, 6th, and 2nd Fleets. They destroyed each fleet one by one, although the 2nd Fleet managed to escape with mostly intact under the command of Yang Wen-li. The battle nonetheless resulted in a major Imperial victory and the Merkatz Fleet took relatively low losses along with the rest of the Imperial forces. (LOGH: 'In the Eternal Night', 'The Battle of Astarte')
The following year, High Admiral Merkatz sided with the nobility of the Lippstadt League during the Imperial Civil War. He and his fleet successfully fought against Admiral Oskar von Reuenthal's forces at the Battle of Schann-tau, although the battle did not have a significant impact on the course of the war. The fleet was then stationed at Geiersburg Fortress. Later, as Duke Otho von Braunschweig and his forces were being routed by Lohengramm outside of Geiersburg, the Merkatz Fleet came out to his rescue, allowing the surviving Lippstadt ships to retreat back to the fortress. (LOGH: 'Courage and Loyalty')
It was presumably disbanded after the civil war, when Merkatz defected to the Free Planets Alliance, although at least one battleship transported Merkatz to Iserlohn Fortress to defect.
|Free Planets Alliance||1st Fleet • 2nd Fleet • 3rd Fleet • 4th Fleet • 5th Fleet • 6th Fleet • 7th Fleet • 8th Fleet • 9th Fleet • 10th Fleet • 11th Fleet • 12th Fleet • 13th Fleet • 14th Fleet • 15th Fleet • Yang Fleet|
|Galactic Empire||Black Lancers • Braunschweig Fleet • Eisenach Fleet • Fahrenheit Fleet • Kempff Fleet • Lohengramm Fleet • Merkatz Fleet • Mittermeyer Fleet • Müller Fleet • Reuenthal Fleet • Wahlen Fleet|