How did the gods in the Slavic pantheon relate to each other?

Question

The Russian Primary Chronicle mentions the Slavic pantheon of Vladimir I of Kiev, possibly an attempt to reform Slavic paganism:

Vladimir then began to reign alone in Kiev, and he set up idols on the hills outside the castle with the hall: one of Perun, made of wood with a head of silver and a mustache of gold, and others of Khors, Dazh'bog, Stribog, Simar'gl, and Mokosh'. The people sacrificed to them, calling them gods, and brought their sons and their daughters to sacrifice them to these devils. They desecrated the earth with their offerings, and the land of Rus' and this hill were defiled with blood.

_{Source: The Russian Primary Chronicle, Laurentian Text, Translated and edited by Samuel Hazzard Cross and Olgerd P. Sherbowitz-Wetzor}

Why did Vladimir pick these gods for his pantheon? How did they relate to each other? Was this the first time they were assembled in a pantheon, or were they grouped together in earlier times?

Answer 1

Any form of speculation onthe Slavic mythology is based on reconstruction. There are absolutely no written records, apart from foreign ones, or some descriptions of the opponents of these beliefs (Christian opponents) describing the Deities et al. Some were retained in folklore, usually as names of tribes of various spirits/daimons etc.

There were various attemps at reconstruction, creating quite interesting compendia, but these are all modern attempts, just like 'Kalevala' - it was compiled in the 19th century in Finland, and is the basis of belief of some neo-pagan groups, but there are no 'ancient records' of the 'Kalevalish' belief-system and practice.

There were several attempts at compiling data from various territories of Slavic people to create compendia of myth and worship (Czesław Białczyński, 'Księga Tura', for example), and perhaps there are of meaning to modern neo-pagan groups.

What is certain is that there were plenty 'local tribe' Deities, for example Swarożyc/Radgost as an Oboritian tribe deity, whether he was worshipped in different territories it is hard to say.

We may speculate that Triglav was to Slavs what Volknut was to the Vikings. Calling Triglav the 'Odin/Woden' of the Slavs would not be a far-fetched scenario, given that Scandinavian and Celtic tribes were present in territory of the Slavs and inter-marriages were not uncommon. If Triglav means 'Three-headed one' it might be a lunar God, the the waxing, waning, full-moon etc. It reminds of Hekate, and the motif of 'three white rabbits' chasing each other in Masonic and Church art.

Perun was the god of lightnings, similar to Zeus amongst Greeks, I would like to classify this god as Jupiterian, but Slavs did not have, as I believe, any form of advanced astronomy like the Graeco-Roman civilization.

As for Dazhbog he was a Solar Deity, thus similar to Helios, Hors(Chors) was his other name.

Wołos (Veles) was the god of cattle and likely the underworld, as was Mokosza (like Hel in the Scandinavian mythology)

Stribog was likely the god of ice and wind.

Sources: Aleksander Bruckner "Mitologia słowiańska"

Answering your question: The 'pantheons' were tribal, there was no 'unified slavic mythology', yet there were Deities more or less extensively known throughout the tribal world of the Slavic peoples. One of the most popular one was a shrine to Sventhevith, were they kept a sacred white steed for divination, localized in modern Germany, Mecklenburg-Vorpommern, Rugen, West of the town of Sassnitz.

To sum up, I would like to cite Plutarch De Iside et Osiride

67. For God is not something without mind or soul, nor is he subservient to men. Consequently we have regarded as gods the beings who use he products of nature and bestow them upon us, providing us with them constantly and sufficiently; nor do we regard the gods as different among different peoples not as barbarian and Greek and as southern and northern. But just as the sun, moon, heaven, earth and sea are common to all, though they are given various names by the varying peoples, so it is with the one reason (logos) which orders these things and the one providence which has charge of them, and the assistant powers which are assigned to everything: they are given different honors and modes of address among different peoples according to custom, and they use hallowed symbols, some of which are obscure and others clearer, directing the thought towards the divine, though not without danger. For some, erring completely, have slipped into superstition, and other, shunning it like a marsh, have unwittingly fallen in turn over the precipice of atheism.

Answer 2

They were grouped together in earlier times - they came from Greece mythology - Perun is Zeus, and Mokosh is Athena. The Slavic world is connected with Greece. Also, the origins of both are unclear but begin from India.

Vladimir picked this pantheon because the Scythians, Thracians and Illyrians were neighbours of Proto-Slavs. The statues were made of wood, like in the Iliad, and they are remains of the bronze age. It reminds me of the Ukrainian meander, 12.000-year-old, and the Vinča culture and Vučedol culture.

Vladimir wanted to be independent and strong, without interference from the church.

Sources:

1. Vedran Sinožić, Naša Troja, (Our Troy), Naklada Uliks, 2016, Rijeka, Croatia.
2. Vedran Sinožić, Kalisto, (IP), Croatia.