The people were led by the Monarch of the Hydran Kingdom, who had many children. However, clear lines of succession were difficult to determine, since the Hydran people were not monogamous. The Hydran Royal Family alone consisted of 30,000 beings, with 1,200 of them being Princes or Princesses.
Despite being a monarchy and having a noble class, the Hydran Kingdom was actually run by the civil service. The bureaucracy was in charge of the day-to-day affairs of the state. Occasionally, the nobility was involved in domestic politics.
Its economy was run by numerous trade guilds, several of which possessed considerable economic power. It was these trade guilds that often determined who became Monarch.
Hydrans were a deeply religious race, whose religion had similarities to animism. They worshipped of a pantheon of minor gods, as well as space-faring beasts. Every household, starship, and military unit or organization had its own god or set of gods.
The military was known for its fighter corps. Hydran warships usually carried more fighters than their counterparts in the Federation or Klingon Empire. Squadrons of fighters complemented their warships firepower. Hydran ships were first armed with fusion beams and gatling phasers, and later, the major starships were equipped with long-range hellbore cannon.
The Hydran Kingdom was frequently at war with the Lyran Empire and the Klingon Empire. Due to their hostile relationship with the Lyrans, the Hydrans had an alliance with the Mirak Star League. The Hydran Kingdom was once conquered by a united Klingon and Lyran invasion force that ruled over them for many years from orbital stations. As the Hydrans were methane breathers, the invaders could not comfortably survive on the surface.
During this time, the Hydran Lost Colonies served as the only independent group of Hydrans. Eventually, the Kingdom was freed thanks to the aid of the Federation. (ST video games: Starfleet Command, Star Fleet Battles)