Enlil, also known as Elil or Nunamnir, is the Mesopotamian god of wind, air, earth, and storms. He was the son of An and Ki, husband of Ninlil and father of Ninurta, Nannar, Nergal, Ninazu, and Enbilulu.
In the several Sumerian myths, such as the Song of the hoe, Enlil is credited in the creation of of the world, by separating the Sky (An) and Earth (Ki) from each other, and the creation of daylight with a hoe made out of gold and lapis lazuli. Enki, his brother, praises the hoe and reproduces it several times, so that every god could have one in the creation of the world. Enlil himself founds Ekur, the divine mountain house and assembly of the Mesopotamian gods.
Enlil fell in love with the goddess Ninlil, and impregnated her with Nannar, the god of the moon. This act angered the other gods, who banished Enlil to Irkalla, the Mesopotamian underworld. Ninlil, now in love with Enlil, followed him into the underworld, where Enlil (disguised as the gatekeeper) seduced her three more times, resulting in three more children being born. These children are Nergal, god of war, plague, death and disease, Ninazu, a god of healing and the underworld, and Enbilulu, god of rivers and canals.
Simliar to Noah's Flood from the Bible, the Mesopotamians had several flood myths, featuring different heroes, such as Atra-Hasis and Utnapishtim. In all these myths it's Enlil who seeks to destroy humanity, as he is annoyed by overpopulation and can't rest because of the noise caused by the humans. He is often depicted as more cruel, seeking humanity's destruction, while his brother Enki helps the heroes survive the flood. Seeing that humanity survived the flood, Enlil decides to spare them, but makes sure that there enough plagues and child mortality to keep the population of humans down.