Culture: Thanian society and culture had advanced to a state similar to that of the middle ages, before they were conquered by the Empire of 1,000,000 Suns. Government was based on a feudal model, with fairly large, settled kingdoms divided into smaller fiefdoms. There were also significant populations of nomadic Thanians. Like the middle ages on Earth, religion tended to dominate Thanian politics, with the largest religion wielding substantial power over the dealings of many of the larger states.
The largest, most influential Thanian religion worships a huge creature, said to be sleeping in the deepest part of the ocean. The trench where the creature is said to lie is so deep that the pressure is too high for Thanians, or even the most advanced submarines to descend. The faithful say that one day the creature will awaken, and ascend to destroy the world.
Tech: Thanian technology was primitive compared to their culture, due to the fact that the native environment of Thanians is underwater. Without fire, metal could not be smelted. Even though some wood-bearing plants could be grown in the shallower areas, wood was rarely used as a building material, and the manufacture of paper was basically impossible. Thanians also did not develop dyes, although the seaweed of their homeworld grew in a wide enough variety of colors for most purposes. Most Thanian tech consisted of stone, seaweed fibers, and the scales, shells, and bones of the local fauna. Bioluminescence also figures prominently in Thanian technology, as many deep-dwelling species produce some form of the phenomenon.
Thanian writing systems are typically achieved by tying knots in cords made of seaweed fiber, similar to the Incan system. Their arts include poetry, drama, and song, with the visual arts lagging behind due to technological limitations, although they do have some, mainly in the form of earthwork sculpture made from stacked earth and stone.
Thanian buildings are made primarily of stone. The first Thanian buildings were communal nests to protect their eggs from predators. These later had storehouses attached to them, and eventually developed into elaborate, underwater castles and temples.
Thanians tend not to wear clothing, but are biologically well adapted to a wide range of temperatures. Their blood contains a natural antifreeze agent.
Thanian warriors generally use two distinct weapons, a double-ended trident, and a net with weights attached around its perimeter. The tridents are traditionally carved from the bones of large fish, although after contact with the outside world, metal and composite models became popular.