Stories tell of women who met untimely ends in the waters of dark lazy rivers, brackish creeks, and the reedy banks of ponds. these stories speak of them as vengeful ghosts of mortal maidens. The stories are wrong, Rusalka are not the spirits of wronged innocents who drowned, but rather their champions and avengers.
In the ancient times, in the rich wet lands of the slavs, Rusalka were small gods given their respect and due. One did not cross a river without tribute, or at least courtesy. In exchange, they gave blessings of protection while crossing, and fertility for those they favored. Yet the Rusalka themselves were never tame, and never completely civilized; thus they could seem ritualistic, yet feral and uninhibited. This conflicting nature made those men of ancient times cautious of them, if also intrigued. Mortal women of those periods, often oppressed and seen as chattal, instead envied even as they too feared.
the sundering came late to the lands of Rus and Pole, of Bulgar and Hungar-but it came hard when it did. The Rusalka were vilified and driven back, until it seemed in all but the most remote areas they vanished.
They're coming back now, drawn by da'an, and drawn by renewed dreams of the unjustly treated, the wishes of those wronged and powerless to find the justice that is their due. Waters are being tainted in the name of greed, and the greedy go unpunished. Rivers seized and owned by the ambitious who in their pride sneer at those they see as lesser. Unlike the mer, while the Rusalka do not like these tainted and polluted waters, they do not fear them, rather they will use the filthy waters like a hangman uses a noose.
If only the other kith would be more reasonable about it , and just let them do their jobs.
Now the Rusalka return seemingly out of nowhere to Concordia. Old blood remembers its power as they undergo dream dances. The Rusalka adapt and adjust as best they may, frustrated at their small numbers. There was a time they worked in twos or threes or even more, to take on their foes, but now they are a rare kith, and must either be solitary, or learn to trust the other kithain who are far more firmly established.
If Rusalka feel a bit alone, it is even harder for the few male among them, just as satyrs were once considered a male only legend, the Rusalka have always been seen as female. Rather male river spirits had different names, even their own kiths, and now that kith is lost, or has merged in with the female branch. While they have been accepted, there is still a strong matriarchal bias among the Rusalka and they're rarely given leadership.