The Mer Kingdom is the collective name for a number of cities, as well as various nomadic tribes of people who live under the sea. It is ruled by King Tiburon R'lyoh IV, his son Mako and his daughters: Ariel and Airelin and its territories sit along the west, south, and eastern sides of the continental shelf surrounding the island of Urt. The northern side is wild and untamed as well as occupied by tribes of sahuagin who periodically test the borders. Its capital city is known on land as Merfolk City.

Though formally called the Mer Kingdom, it is in actuality more of a loose collection of independent tribes and villages that King Tiburon I managed to unite. It is said the people of the Mer Kingdom have similar religious practices to the Spirits of Nature worshippers, though they have their own varieties. Most of the population consists of Merfolk, with a minority of Aquatic Elves and Aventi also present, though not entirely on equal footing

There seems to be at least two maids to every man in the merfolk population and arcane casters seem to be rather rare. Most of the casters are divine being cleric or druid with some bards and the occasional sorcerer making up the rest of the magic users. The kingdom currently doesn't have a magical tower of it's own as, at the moment, there seems to be no need. This may change in the near future as there are possibilities that the sahuagin in the SRR may ally with the ones in the north and do a massive attack - a mage tower may be required for defense.