Religious event
Island after island, archipelago after archipelago, and neither of them suited the refugees. Even among the ohtrim, each time the wonder settled, it was soon followed by disappointment. Too small, too dangerous, no usable materials to erect a city, no fertile soil...
Although Lilish "The young" found inspiration again by writing Row until the shore and The Voyage of the Whispering Wind, it wasn't enough to lift the mood of her people for more than two weeks.
Moreover, the experienced sailors started to notice strange currents that led the boat in a given direction. They corrected their trajectory, trying to follow their fellow Elrim and they managed to do it pretty well.
However, they found out that those strange flutuations led to one geographical point. With some basic geometry, the ohtrim figured out that it was none other than the first well who collapsed into a giant maelstrom.
This last discovery saddened every ohtrim, and added to the ambiant morosity. In response, a belief was formed: The presumed deceased empress of the Elrim had rised again to channel the first well. This thought ran wild in several artists of the ohtan fleet.
The most recurring depiction of such a being was an half elf, half-humanoid with fishlike features, thus leading to the creation of a goddess: The Sunken Goddess.