Irij

Vyraj (Belarusian: Вырай, Polish: Wyraj), Iriy, Vyriy (Ukrainian: Вирій, Russian: Ирий, Ирей, Вырий), or Irij (Croatian: Irij, Czech: Irij, Slovak: Irij, Serbian: Ириј), is a mythical place in Slavic mythology where "birds fly for the winter and souls go after death" that is sometimes identified with paradise. It was said that spring arrived on Earth from Vyraj.

Initially, the Early Slavs believed in only one Vyraj, connected to the deity known as Rod—it was apparently located far away beyond the sea, at the end of the Milky Way. It was often imagined as a garden beyond an iron gate that barred the living from entering, located in the crown of the cosmic tree. Whereas the branches were said to be nested by the birds, who were usually identified as human souls. According to folkloristic fables, the gates of Vyraj were guarded by Veles, who sometimes took the animal form of a raróg, grasping in its claws the keys to the otherworlds.

The pagan Slavic peoples thought the birds flying away to Vyraj for the winter and returning to Earth for the spring to be human souls. According to some folk tales, the human soul departs the Earth for Vyraj during the cremation of its deceased flesh on a pyre; however, it does not stay in paradise forever, returning some time later to the womb of an enceinte woman (traces of reincarnation can be seen in this belief)—carried by a stork or nightjar.

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Wikipedia