The Reef Council

Before the waters of the world seep into the Maelstrom, the waves are guarded by an alliance known as the Mainland Pact. When Oxchester lost its fellow Oathbound Kings, they turned to their aquatic neighbors. Generally known as the Reef Council, the Sea Elves, Saughain, Iocatha, Kuo Toa and Tritons make their mark on the world by a constant vigilance kept on the maelstrom. They are more concerned with the maelstrom than the mainlanders but when Oxchester needed help to survive, they made a pact. Oxchester required food and wealth to trade with the fledgling Empire and would trade their secret magics of Exorcism to the mages of the Reef and a promise of help once their technology had reached a point. The Pact was made and the Council quickly incorporated the rituals into their own magical training. As time passed, the Reef Council has grown smaller and the depths it once protected have been lost to encroaching monsters. All seemed dire until the technology of Iron Vessels allowed for the Oxchesters to efficiently aid in the fight.
Life beneath the waves is focused towards resisting the Maelstrom but it is not monocultural. Kuo Toa Chanters are some of the greatest mages the world has ever seen, rumored to conjure godlike beings. The Iocatha have a natural propensity for eloquence and are ambassadors, politicians and playwrights classically. The Sea Elves have long traditions as craftsmen and have been recently saught after for engineering the Iron Vessels in Oxchester. Tritons form the main military class, both commanders and frontline fighters against the Maelstrom, less of full on war but more like highly trained response variables to specific threats.
Finally, the most populus Saughain fill a generalist role from hunters to messengers. If you have a buisness, you likely have saughain working for you

We are the wall between safety and oblivion