The Babylonians were polytheists who were heavily influenced by Sumerian culture, creating a complex pantheon of gods, demons, and others. Many Babylonian myths were designed to tie into this pantheon in some way, describing the way in which the gods made the world, and providing explanations for the events of life on Earth. Some of these legends and myths have become quite famous in their own right. For example, The Epic of Gilgamesh, which describes the doings of some of the gods, is a notable piece of Mesopotamian literature.
As with most pantheons, the Babylonian gods were headed by two gods, in this case Apsu and Tiamat. All of the Babylonian gods are descended from this original pair, with an interesting twist. According to legend, these Babylonian gods did a poor job of looking after their children, leading to a revolt which ended when Ea slew Apsu while Tiamat did nothing.
Allegedly, each succeeding generation of Babylonian gods was superior to the last, culminating in Marduk, the god of wisdom, who became the eventual ruler of the gods. Babylonians celebrated the annual death and rebirth of Marduk each year as part of their religious faith. Marduk also ultimately overcame the forces of Tiamat when she was finally stirred to action, and in conquering Tiamat and her forces, led by the god Kingu, Marduk made the world, along with people to live in it.
To name all of the Babylonian gods and their complex relationships would require much more space, but some of the gods are particularly notable or interesting. Sin, for example, is the moon god, and the father of Shamash, the god of the poor and travelers. Nintu and Anu are both creating gods, with the ability to make things such as the winds, while Kingu's blood was used to make mankind. Damkina is the Babylonian earth mother, wife of Ea, another god of wisdom who also oversaw the arts. Mummu was another god who became renowned as a craftsman.
The god of air was Enlil, and he also looked after the weather. Ishtar, the goddess of both love and war, became famous for venturing to the underworld to get her lover back, mirroring a number of other myths from around the Mediterranean in which someone makes the sacrifice of entering the underworld to redeem someone else's life. It is also intriguing to note that while love and war seem antithetical in many modern eyes, Ishtar was far from being the only goddess of love and war in the Mediterranean, suggesting that early civilizations in this area recognized the intense emotions which could accompany both experiences.