In ancient Slavic religion , the thunder god.
He purified the earth and made it fertile, and he was the overseer of right and order. His powers were believed to be evident in the thunderbolt, the rattle of stones, the bellow of a bull, the bleat of a goat, and the touch of an ax blade. In the Christian period the worship of Perun was gradually transferred to St. Elijah, but folk belief in his powers continued. Sacrifices and communal feasts on July 20 in his honor were celebrated in Russia until modern times.