In his work on the Slavic mythology ethnographer and folklorist Eugeny Georgievich Kagarov (1882-1942) put a special accent at the folk rites, which form the main object of his research. The author noted that approached the theme as historian of religion, not as a Slavist.
In the first part of the book, ‘Low mythology (conception of spirits)’, the author calls Animatism the first step of Slavic religion. Later, Animatism was transformed into Animism. The author gives a classification of lower spirits and characterizes each group: 1) spirits of things and natural phenomena (Rusalka, Leshyi, Vodyanoi, etc.); 2) spirits-protectors of certain fields of material culture (ritual figures); 3) clan and family spirits (Domovoy); 4) demons of illnesses, nightmares, etc. In the final sections he gives different points of view by western scholars of his time at the origin of beliefs in werewolves.
The second part, ‘Higher deities’, is on the Slavic pantheon, where only Perun seems the author reliable from a point of historical truth. For the other gods K. made references at the ‘Tale of Igor’s Campaign’. On his opinion, there were not such gods as Mokosh, Lada, and Simargl at Slavs.
In the third part, Folk festival rites’, the author analyzes Slavic calendar feasts assorted according the seasons. He put a special attention to the feasts of Kolyada, Ovsen’, Shrovetide, Kupalii. The author gives references at A. N. Veselovsky, E. V. Anichkov and others.
The fourth part, ‘Conceptions of soul, funeral rites, cult of ancestors’, is started with enumeration of various images of soul in different traditions. Then, the author gives a list of variants of burials connected with different views on deceased: as ‘unclean’ and evil – or protectors and assistants.
In Slavic religion the author finds numerous parallels with other religions, including classic ones, on which K. defended his Master thesis. “Religion of Old Slavs’ is not big, but very capacious essay on Slavic religion – partly obsolete, but interesting is a wholesome view on the theme, presenting a specific step in studying pre-Christian Slavic religion.