The Quest for Immortality & Its Limit
A king who would not die learns the hardest wisdom: immortality is the gods' alone — but a name endures.
Also: immortality · Gilgamesh · Gilgameš · quest for eternal life · Utnapishtim · plant of life · Epic of Gilgamesh · death of Enkidu
The Epic of Gilgamesh is, at its heart, a meditation on mortality. After his beloved companion Enkidu dies, the hero Gilgamesh, terrified of his own death, roams the earth in search of eternal life. He finds the Flood-survivor Utnapishtim, who tells him that the gods reserved immortality for themselves; even the plant of rejuvenation Gilgamesh wins is stolen by a snake. He returns home empty-handed but wiser, his lasting achievement the great walls of his city. The epic's answer is sober and humane: a person cannot escape death, but can leave a name and lasting works behind.
In short
The central theme of the Gilgameš epic: the hero's search for eternal life after his friend's death, and his discovery that immortality belongs to the gods alone, leaving lasting name and good works as humanity's portion.
Where it’s found
Standard Babylonian Gilgameš, esp. Tablets IX–XI (akkadian-pending; George, The Babylonian Gilgamesh Epic); Sumerian 'The death of Gilgameš' (ETCSL 1.8.1.3, in corpus) treats his mortality
How the idea developed across Sumer, Babylon & Assyria
The immortality theme is sharpened in the Standard Babylonian recension (traditionally redacted by Sîn-lēqi-unninni) over the Old Babylonian forebears; the wall-of-Uruk framing (a lasting name) bookends the SB epic. Composition vs manuscript: an SB composite from first-millennium tablets built on older material (George).
Gilgameš is a LEGENDARY/epic figure (a king of Uruk in the King List, possible historical kernel, known through legend) — not to be presented as a documented historical person.