The Epic of Gilgamesh, an epic poem from Mesopotamia, is considered the world's first truly great work of literature.  The literary history of Gilgamesh begins with five Sumerian poems about 'Bilgamesh' (Sumerian for 'Gilgamesh'), king of Uruk. These independent stories were used as source material for a combined epic. The first surviving version of this combined epic, known as the "Old Babylonian" version, dates to the 18th century BC and is titled after its incipit, Shūtur eli sharrī ("Surpassing All Other Kings"). Only a few tablets of it have survived. The later "Standard" version dates from the 13th to the 10th centuries BC and bears the incipit Sha naqba īmuru ("He who Saw the Deep", in modern terms: 'He who Sees the Unknown). Approximately two thirds of this longer, twelve-tablet version have been recovered. Some of the best copies were discovered in the library ruins of the 7th-century BC Assyrian king Ashurbanipal.