There are no primary written sources concerning Slavic mythology–no myths written in the original languages, no poems, or songs, or tales of gods and heroes.  The first people to write about the Slavic faith were Christian proselytizer, and their accounts are naturally hostile to the pagan faith. This means that we know tantalizing hints about Slavic deities from archaeology and we have some hair raising accounts from Christian sources (which are probably slander), but we actually know very little.  One of the deities who has gained the most mileage from this dearth of information is the dark accursed god Chernobog (aka Crnobog, Czernobóg, Černobog, Црнобог, Zernebog and Чернобог).

Chernobog!
A German priest traveling among unconverted Wendish and Polabian tribes wrote about Chernobog as a god of woe whose name meant “black god”.  The name also shows up in a smattering of other sources which reveal little–but other than that Chernobog is largely unknown.  While this would be a big problem for a harvest god or a love goddess, Chernobog is an underworld deity and his mysterious nature has made him popular with artists, movie makers, and video game producers looking for a big scary guy who doesn’t talk too much.

Chernabog from Walt Disney's "Fantasia"

The most famous Chernobog appearance was in the Walt Disney film Fantasia, where he starred (as “Chernabog”) in the animated “Night on Bald Mountain” sequence. As Modest Mussorgsky’s wild tempestuous music plays, Chernabog, a huge winged demon of blackness, summons forth evil spirits and the restless undead to a lightning scarred mountain top (only to be banished by dawn and the ringing of a church bell).   The sequence made a huge impact on me when I saw it on VHS in music class in elementary school and apparently I am not alone,  Wikipedia had a long list of fantasy writers who have since used the character as a villain (the most intriguing-sounding of which was an alternate history of Russia where a comet impact had caused widespread famine and cannibalism and Chernobog was worshipped as a major deity!).

"Chernobog" (artwork by by Cristopher Erik Thompson)

Perspicacious readers will probably notice I have just written a post concerning deities of the underworld based on almost no real information other than modern fantasy/entertainment–but there is a useful lesson here.  If you are stuck for material Chernobog is your man–his fearsome aura of mystery and dreadful (albeit ambiguous) name will do your work for you.

Aaargh!