Chenga was a neutral planet with a small population, originally from Earth.
Chenga was settled some 200 years before the Intergalactic War, at which point the population split into two groups: the Primitives wanted to live a simple life in the forests, but the Hitechs intended to make full use of all technological developments.
Eventually the Hitechs began using the Primitives as unwilling sources of organs and tissue for medical purposes. Hitech hunters were paid a bounty for each captive they delivered to a dome known as 'the Slaughterhouse' where organs were harvested for transplant (humanely, of course). During the War, Chengan hospital ships collected survivors to be taken back to their homeworld for the same purpose.
Vila Restal's life rocket landed on Chenga where he met two Primitives, Lom and Mall. Despite their attempts to help him he was taken to the Slaughterhouse by two Hitech hunters, Zee and Barr. There he met Cally and Servalan who had been picked up by a Chengan hospital ship.
Servalan was able to negotiate her release from the Slaughterhouse by promising the Chengans a large Federation aid package in return for her freedom. Vila and Cally were on the verge of having their organs harvested when the Liberator entered teleport range and they were picked up. (C: Powerplay)