The Enuma Elish is a Babylonian religious text from either 1800 BCE or 1100 BCE, depending on which scholar you ask. The text is believed to be a ritual text, likely meant to be read aloud during the Babylonian New Year festival. The story tells of an epic battle among the gods, centered around Marduk, the king of the gods, and his defeat of Tiamat, the being of chaotic waters. These stories also include a creation account, telling how the earth came to exist.
The discovery of the text in the late 19th century was largely impactful in the historical approach to ancient texts, especially the study of the Bible, because the stories of the Babylonian empire share uncanny similarities to the Hebrew account. In fact, later studies have shown that the Hebrew scriptures drew largely from the Enuma Elish, even appropriating quotes originally about Marduk, but using them to glorify the Hebrew God, Yahweh. There are also accounts of Yahweh creating the world in the same manner as Marduk was alleged to have done, by cutting a cosmic serpent in half and using the halves to fashion the sky and waters.
Tiamat is angered by the death of her husband, so she remarries and exalts her new husband, Kingu, to the position of supreme dominion. She does this by fashioning eleven beasts: a venomous snake, a great serpent, an exalted serpent, a furious snake, a hairy thing, a beast of weather, an angry lion, a scorpion-man, a being of violent storms, a fish-man and a bull-man. Marduk then conquers her, defeating her beasts. He rips Tiamat in two, which is the action responsible for the creation of the realm where the humans live.