Was Zeus a compilation of gods?

Question

Zeus is a complex character; although he is chief among gods, with many noble qualities, he is also deeply flawed. Among various sites on the internet 1 2 3 4, there's this passage which suggests that he is a compilation of various supreme gods:

Zeus was mighty, glorious, awesome and wise, although he did show a certain degree of surprising foolishness and naiveness when it came to hiding his love affairs. Some historians attribute this less than noble behavior of the "noblest one of all" to the fact that Zeus was most likely a compilation of many "supreme gods" from different areas. When his worship spread to an area which already worshipped another god, some of that god’s qualities as well as his wife or lover were transferred to Zeus. Aside from the endless affairs Zeus was different from other gods in that he did not participate in the arguments and the resulting petty scheming that made up the daily activities of other gods. Being this wise ruler, he also demanded just and righteous action from men. Zeus was however vengeful, as can be seen in The creation of man by Prometheus, but only rightly so.

Unfortunately, this passage is unsourced and those sites might all be plagiarising some unknown, original source.

Is this assertion true, was Zeus a compilation of other gods, combining their qualities? If so, do we know which gods became lumped into Zeus, and what were they like?

Answer 1

I haven't heard quite that theory.

The theory about the Original source of Zeus that I tend to come across^* is that the original proto-Indo-European people (PIE), based on comparative linguistic and religion studies, appear to have likely had a pantheon headed up by *Dyeus Ph2ter (Sky Father). They also had a thunder and/or Oak god *Perkwunos.

The Greeks are of course Indo-European descendants, and Zeus is both a fairly typical exemplar of the Sky Father god, and seems to have taken on the attributes of the thunder god (the thunderbolts are kind of a dead giveaway). Oaks are also said to be sacred to Zeus in many sources, particularly at Dodona. So he appears to be a combination of both the PIE Dyeus and Perkwunos. Somehow, both got merged into one god.

^{* - The go-to reference for this appears to be The Oxford Introduction to Proto-Indo-European and the Proto-Indo-European World}

Answer 2

Dyeus Phater is Everywhere

To "Yes, and..." off TEDs answer - the Dyeus Phater probably originated North of the Black Sea around 3,500 BC, and he spread to a remarkable number of places. There are echos of Dyeus in the Vedic Indra and the Irish Dagda, for example.

Proto-Anatolian broke off PIE around 3,000BC, and Proto-Greek around 2,000BC as waves of PIE migrants spread out from their homeland (probably modern day Ukraine). By the time the Iliad was written (circa 800 BC) the idea of Dyeus was nearly 3000 years old!

So both the Greeks and the Trojans would have worshiped a Sky God that descended from Dyeus, but these gods would have had around 2,000 years to drift apart.

The chief deities of these two groups would have had many common attributes, but would have had distinct personalities and stories - which might not seem consistent when merged, but human nature is to steal good stories, so the best tales from the two cultures would surely be "traded."

More Zeus Analogues

I used the example of Greek and Anatolian mythology above, but its worth remembering that Proto-Italic, Proto-Balto-Slavic (including Macedonian), Proto-Albanian, Proto-Celtic, and Proto-German are all PIE languages.

Greek speakers would have seen Zeus analogues all around them, because all those cultures had some deity descendant from Dyeus Phater - but the all had their own, divergent history. It seems likely that the Greeks may have absorbed some of the personality of those neighboring Zeus' over time - which can lead to a kind of fractured personality.

So yes, there were probably many different traditions that the Greeks would have recognized as "Zeus-like" and may have contributed to Zeus' overall mythology.