'Chernobog (Latin: Zcerneboch, lit. "Black God", reconstructed as *Čьrnobogъ, from *čьrnъ ("black") + *bogъ ("god") is the god of bad fate worshipped by the Polabian Slavs. He is first mentioned by Helmold in the Chronica Slavorum. The authenticity of the cult of the Chernobog, as well as of the Belebog reproduced by analogy to him, is controversial among scholars. Nevertheless, Chernobog is one of the most popular Slavic gods in the world.
The German monk and chronicler Helmold, who accompanied the Christianization missions against the Elbe Slavs, describes in his Chronicle of the Slavs the cult of Chernobog:
Also, the Slavs have a strange delusion. At their feasts and carousals, they pass about a bowl over which they utter words, I should not say of consecration but of execration, in the name of [two] gods—of the good one, as well as of the bad one—professing that all propitious fortune is arranged by the good god, adverse, by the bad god. Hence, also, in their language they call the bad god Diabol, or Zcerneboch, that is, the black god.
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