Was the mith of the King Gilgamesh impact on how the Mesopotamia chiefdoms develpoed their political systems and maybe the way rulers or kings where viewed as deities?
The epic of Gilgamesh, one of (if not the earliest) Western texts, was a popular story for thousands of years. In the ruins of ancient libraries, archaeologists have discovered several different versions of the story, which seems to have had several revisions over time. The most prominent feature that would be significant to us is the story of the Flood; scholars agree that the Biblical Flood story was actually a Hebraic interpretation of the Gilgamesh text.
The myth of Gilgamesh represents one of the earliest forms of mankind forming a civilisation and centralising power. As such, it is particularly interesting for Diamond in his study of civilisation and how some civilisations were more powerful than others and able to gain dominance over other groups. Clearly linked to the success of Gilgamesh was the way that he was viewed as a deity and how this was utilised effectively to maintain power.
To me, the importance of this myth is to be seen more in its impact on the Judaeo-Christian tradition. The Old Testament has many places with similarities to the myth of Gilgamesh. It is hard to say for sure if the myth influenced by the Bible, but it seems likely. If it did, this would be a major way in which the myth is important for Western Civilization.