The Drallan Empire is the first interstellar Vaikan faction that has long since gone extinct. Their downfall led to a dark age in the Vaikan states until the Karalian Empire rose up and began reconquering old systems.
Generations after entering space, much of the Drallan Empire started to do away with religion, banning the worship of the Jamzezist pantheon and brainwashing anyone who did not comply. Materialism, pleasure and the worship of celebrities became the dominant practices.
The Drallan Empire was known for its advanced studies in artificial intelligence. Throughout their early history, they had managed to replace manual labor entirely, having robots do all of the work. This left the majority of citizens with 100% leisure time, eventually transforming them into a hedonistic society.
Over the course of the centuries in this pseudo-utopia, the citizens of the Drallan Empire eventually either forgot or did not care how to do manual labor or even maintain the systems due to the lack of prior planning and accountability of failsafes. Because of the lack of maintenance, the system shut down isolating the Drallan colonies from each other with almost none of their technology working. And since very few actually knew how to survive without the technology, billions of Vaikan gradually died one by one of starvation and infighting.
As a result of this great black out, much of the Vaikan species reverted back to a pre-industrial state until they relearned how to use the lost technology from their ancestors.