Procopius of Caesarea and Thietmar’s Chronicle
The sixth-century CE writer Procopius of Caesarea (De hello gothico [On the Gothic War] 3.14.23-4) is the first author to discuss Slavic religion. He mentions two Slavic tribes, the Sclavinoi and Anthoi (who were dwelling somewhere in the Dniestr and Dnepr region at that time), and states that they worshipped as their main deity a god of thunder, astrapes demiurgos (literally “creator of lightning”).
Procopius furthermore notes that “they revere, however, both rivers and nymphs (potamous te kai nymphas) and some other spirits, and they also sacrifice to all of these, and perform divinations in connection with these sacrifices”. This earliest available written source on Slavic religion portrays a tradition reminiscent of early Germanic religion, where water played an important role in offerings and divinations. The water spirits mentioned by Procopius as nymphas kai alia atta daimonia are rarely attested in later sources and reappear only in very late accounts and in folklore (Gieysztor 2006: 257-9). The goddess Mokosh who appears in Old Russian written sources (and in various toponyms) could, however, be connected with the idea of wetland or rather “wet, fertile soil” and could thus be identified with the mat’ syraia zemlya (“damp mother earth”) of Russian folklore.2 Although the interpretation is uncertain, some archaeological evidence may corroborate this information. On some of the oldest known Slavic pottery there are scenes with a possible mythological reference, including a rider who appears with a kind of superposed zigzag marking; this could be interpreted as a weather god with a lightning bolt in his hand (Moszczyriski & Szymanski 1987). Similarly, wave motifs are frequent on early Slavic pottery and could perhaps be connected with aquatic symbolism.After Procopius’s account, there is a gap in the sources concerning Slavic religion lasting for about four centuries.
During this period the written evidence concerning Slavic pre-Christian religion consists of little more than some glosses. From the beginning of the eleventh century, however, Thietmar’s Chronicle and a number of other accounts from the next two centuries provide us with a relatively large corpus of material. One must, however, appreciate that this set of information belongs to a new and very different period, a different historical context, and comes from a distinct region populated by Western Slavs, mostly Polabians, who had at that time been forcibly converted to Christianity by Germans, Poles and Danes.Thietmar’s Chronicle (1.3), written in the early eleventh century, informs us of the existence of a kind of “holy spring” called Glomac, located two miles from the river Elbe. This, he writes, was the most important sanctuary of a Polabian tribe, the Daleminci-Glomaci. According to Thietmar, “the whole country extending from the Elbe to the river Caminizi got its name from the spring”. The notion “spring” is a bit misleading here. Thietmar later explains that it was in fact a large bog. There, Thietmar wrote,
as the people from the area and the witnesses claim, strange events happen. As long as the natives enjoy the blessing of peace and the soil allows adequate harvests, the morass is covered with wheat, oats and acorns and gives joy to the neighbours who crowd around it. Whenever a war rages, blood and ash inevitably foretell the future. Each inhabitant reveres and respects that spring more than any churches, although what he can expect from it is quite uncertain.
Thietmar calls the phenomena he describes “miracles”. But the Glomac marshes were used from time to time as an arena for offerings, in times of peace as well as war. The deposits of agricultural products suggest symbolism related to an abundance of food for people (wheat), horses (oats) and pigs (acorns). Blood and ashes suggest burnt offerings of animals (or even people).