The book proposes a new reconstruction of East Slavic paganism, challenging both the conclusions of Academician B. A. Rybakov and the system of V. V. Ivanov - V. N. Toporov. The author, a famous Russian archaeologist and philologist, discovered in Chechen-Ingush folklore mythical legends about Perun, brought to the Caucasus a thousand years ago by the resettlement of the Slavs during the vicissitudes of the Arab conquests. He compares these data with Russian fairy tales (in particular about Tsar Saltan), beliefs about witches and mermaids, and chronicle legend. Perun appears in this reconstruction as the main god of the Slavs from the category of dying and resurrecting deities, similar to Apollo and associated with the sexual cult of fertility. The so-called Veles book and archaeological data are analyzed in detail. The topic has recently acquired relevance in connection with the spread of nationalist neo-paganism and the general revival of the dispute between the Pochvenniks and Westerners about the uniqueness of the cultural development of Russia.