King Hammurabi ruled the Babylonian Empire from 1792-1750 BC and brought Mesopotamia under the control of one leader.
He helped unite his empire by publishing the Code of Hammurabi. His Code is considered to be history's first known written set of laws.
The Code emphasized retribution (or pay-back) and had punishments that varied according to a person's social status (stricter if you're poorer). Hammurabi had his Code carved (using cuneiform) into a stone pillar and put in a public place for everyone to see. This meant you couldn't plead ignorance of the law, unless, well, you couldn't read.
The Code did offer protection to all classes of Babylonian society and tried to protect the weak and the poor, including women, children, and slaves, against injustice at the hands of the rich and powerful. The laws were numbered 1-282, but numbers 13, 66–99, 110, and 111 are missing.
Eye for an eye... OK... your turn...
Law #6: If anyone steals the property of a temple, he shall be put to death. The one who receives the stolen things shall also be put to death.
Law #129: If a man's wife be caught with another man, both shall be tied and thrown into the water. The husband may pardon his wife, however.
Law #157: If anyone be guilty of incest with his mother, both shall be burned.
Law #192: If a son says to his adoptive father or mother: "You are not my father or mother," then his tongue shall be cut off.
Law #194: If a man gives his child to a nurse, and the child dies in her hands, her breasts shall be cut off.
Law #195: If a son strikes his father, his hands shall be cut off.
Law #196: If a man puts out the eye of another man, his eye shall be put out.
Law #199: If a man put out the eye or break the bone of another man's slave, he shall pay one-half of its value.
Law #205: If a slave strikes the body of a freed man, his ear shall be cut off.
Law #209: If a man strikes a pregnant woman so that she loses her unborn child, he shall pay her 10 shekels.
Law #210: If the woman dies, his daughter shall be put to death.
Law #218: If a physician kills a patient, his hands shall be cut off.