Generations ago, religious people built a colony spaceship called 'Jehovah'. A planet called Samaria was established. The colony ship, orbiting above, was able to provide supplies and services. These were accessed by genetically modified 'angels', who were the only ones capable of performing the right vocal tones.
Over the generations, the concept of the ship was forgotten and it was believed Jehovah was an actual deity. Now factions of 'angels' fight against rebel forces called 'Jacobites'. The angels want to keep their power and the Jacobites wish to know the truth.