Next to nothing is known of the history of the Kimer, as they have never developed written language of their own. Only in the last few hundred years have some Kimer began writing, using the languages of Human explorers that have contacted them. What is known is from the histories of other races, where Kimer do make the occasional appearance. They are attested in the oldest reliable Elven sources, from the time of colonization, and were likely around for thousands of years prior, as they seem to already be in every place the Elves in those stories travel to. However, details of these early meetings are very scant, as the Kimer even today do not typically have much interaction with outsiders - Although that is changing due to the efforts of some adventurous Humans.
Kimer are of approximately Human build, with a distinct blue or greenish color to their skin and hair. They can breathe comfortably both underwater and in the air, but they do not do well in very dry climates and must seek water or risk dehydration and death. Many Kimer have an intuitive understanding of magic which makes them quick studies as Mages. Their lifespan is approximately 100 years.
While not distrustful of outsiders in the same fashion as Dwarves, most Kimer rarely interact with the other civilized races as they spend little time on land. A common misconception is that Kimer cities are located in the middle of the ocean far from the shores. In fact, Kimer towns and cities are always located within a few miles of the shoreline, and they rarely venture to the ocean depths. This is largely due to the extremely dangerous creatures that lurk in those dark places.
Kimer are typically free spirited by Human standards, and do not look too fondly on authority figures. They nonetheless do have large cities with many thousands of inhabitants. Most Kimer are known to engage in a religion centered around Ancestor Worship. They are uncharacteristically secretive about this to outsiders, but it is known that they call upon the spirits of particularly famous or influential ancestors before important events, while closer relatives are usually called for more day to day tasks.
Kimer cities are usually not governed by any individual group, but rather each district or ward will have its own ruling body. Occasionally these groups, sometimes little more than gangs, will engage in turf wars, but this is largely the extent of conflict in Kimer society, which does not know large scale wars. Luckily for them, other races are unable to mount significant attacks on their underwater homes.