Gilgamesh

King Gilgamesh lived and reigned about 2700 BC.

According to the Sumerian king list, he was the fourth king of Uruk in Sumer and he was succeeded by his son Ur-Nungal who ruled for 30 years:

Gilgamec, whose father was a phantom (?), the lord of Kulaba, ruled for 126 years.

He built a temple to Ninlil in Nippur, and possibly the walls of Uruk.

The Epic of Gilgamesh

The Epic of Gilgamesh is from Babylonia, dating from long after the time that Gilgamesh was supposed to have ruled. It was based on earlier Sumerian legends of Gilgamesh. The most complete version of the epic was preserved in the collection of the 7th century BC Assyrian king Ashurbanipal.

Based on a summary of the Epic -- http://www.wsu.edu/~dee/MESO/GILG.HTM, the contents of the eleven stone tablets are:

Introducing Gilgamesh of Uruk, the greatest king on earth, two-thirds god and one-third human, the strongest super-human who ever existed. But his people complain that he is too harsh, so the sky-god Anu creates the wild-man Enkidu. Enkidu is tamed by the temple harlot Shamhat.
Enkidu fights Gilgamesh but loses, they become friends. Gilgamesh proposes the adventure of the cedar forest.
Preparation for the adventure of the cedar forest; many give support, including the sun-god Shamash.
Journey of Gilgamesh and Enkidu ot the cedar forest.
Gilgamesh and Enkidu, with help from Shamash, kill Humbaba, the demon guardian of the trees, then cut down the trees which they float as a raft back to Uruk.
Gilgamesh rejects the sexual advances of the goddess Ishtar. Ishtar gets her father, the sky-god Anu, to send the "Bull of Heaven" to avenge Gilgamesh and his city. Gilgamesh and Enkidu kill the bull.
The gods decide that somebody has to be punished for killing Humbaba and the Bull of Heaven, and it's Enkidu. Enkidu becomes ill and describes hell as he is dying.
Lament of Gilgamesh for Enkidu.
Gilgamesh fears death, decides to seek eternal life by making a perilous journey to visit Utnapishtim and his wife, the only immortal humans, alive since before the Great Flood.
Completion of the journey, by punting across the Waters of Death with Urshanabi, the ferryman.
Gilgamesh meets Utnapishtim, who tells him about the Great Flood and gives him two chances for immortality. Gilgamesh blunders both chances and returns to Uruk.

Although the epic itself was lost for millennia, and is not widely know today, it has had a powerful impact on Western literature. It is likely that the Biblical story of Noah and the flood is a retelling of a portion of the Gilgamesh epic.

Sumerian legends of Gilgamesh