The Aesdherians are an alien race.
In Ancient-Shivan War
Before their war with the Ancients, the Aesdherians fought and defeated another alien race in what was described as a bloody conflict, where the Aesdherians developed their beam technology and enhanced their armor. They had little time to celebrate their victory, however, as the Ancients attacked them, without warning and with a clear intent to kill.
It is suggested that the Ancients were playing with them, hoping that the Aesdherians would prove a worthy foe. Since the Aesdherians showed slowing signs of technological progress, the Core decreed that they were to be exterminated. The Sopul Fleet, led by Fleetmaster Im'Halus aboard the carrier Akrotiri, launched a final offensive on the Aesdherians and crushed their fleets in the Battle of Aesdher. Aesdher IV, their homeworld, was subsequently attacked from orbit and the entire Aesdherian race was eventually extinct.
Ancient intelligence believed that the Aesdherians had developed rapidly, and deduced that they already battled and won a war against another sentient race. Aesdherian fighters were also equipped with shielding, unlike the Ancients. However, their shields were insufficient to effectively counter Ancient weapons, and Aesdherian beam weapons posed only a minimal threat to Ancient warship hulls.
In Rekt Galaxies (Mortal Engines)
- Tech room description in Blue Planet makes veiled reference to the discovery of the remains of a civilization destroyed by the Ancients, which could be taken as a tribute to the Aesdherians and Ancient-Shivan War.
- Ancient-Shivan War
- Rekt Galaxies