The rusalka

A water spirit of Russian, Ukrainian and Belarusian folk belief, held to be the soul of a girl who died before marrying or of a child who died unbaptised.

Culture.RF, the Russian culture ministry's portal, says Russians, Ukrainians and Belarusians saw rusalki as the spirits of girls who died before their wedding, or of children cursed by their mothers. In some places any drowned woman was thought to become one, and in another version children who died unbaptised became mavki. The spirits visited the living during Rusalka Week, on Ivan Kupala or before St Peter's Day. In the Russian North people said they also came in winter, for example out of a hole in the ice.

Jan Máchal, writing in 1918, says the rusalky closely resemble the navky and that belief in them was most widespread among Russians. He records them as children who died unbaptised, drowned or smothered, or as girls and newly married women who died unnatural deaths or were cursed by their parents. They might look seven years old, or like young women in their prime. The Encyclopedia of Ukraine describes the Ukrainian rusalka as a pretty, long-haired girl who stands for the spirit of a girl who drowned or of a child who died unbaptised. In that account she goes naked under her hair or in a shift, with a wreath of sedge, and the rusalky live together in crystal palaces on river beds, coming up only in spring, at Rosalia, on Green Thursday or at rusalka Easter.

Máchal also describes ceremonies that end with a doll, called Rusalka, being thrown in the water or burned. He reads the rite as probably a second funeral, meant to win over the spirits of people who died violently and were buried without religious rites. Wikipedia says 19th-century versions treat the rusalka as a restless, dangerous dead being tied to the unclean spirit. It cites Dmitry Zelenin: young women who drowned themselves after an unhappy marriage, or who were drowned against their will, had to spend their allotted span on earth as rusalki.