Before man-made law, the only law was the law of nature or the law of the jungle. Only the strongest survived. For a long time, man lived by the same law, using violence to assert dominion over others.

An eye for an eye - Hammurabi's Code

Hammurabi was the king of Babylon, a city state in Mesopotamia in 18th century BC. Mesopotamia is the cradle of human civilisation, and it is from this area that the first story - the Epic of Gilgamesh - was written. Babylon was only a small kingdom when Hammurabi first came to the throne, but through several military victories, he managed to expand it. Despite his military prowess, Hammurabi is best remembered today as a law maker. Hammurabi's Code is the oldest set of laws in recorded history. It is formed on the idea of retaliation and retribution - an idea that can also be found in ancient Hebrew laws.

In Hammurabi's Code, not everyone was equal before the law as we are today; instead, people were separated into three classes: free men and women (patricians), commoners (plebeians), and slaves. Depending on who committed a crime against whom, the level of retribution varied. For instance, if a man hit a pregnant woman and she miscarried, he would pay her 10 coins in compensation if she was a free woman. However, if that woman was of the plebeian class, then the compensation would be five coins. And, if she was a slave, the compensation would be two coins.

However, the legacy of Hammurabi's Code is the idea of retaliation - the infamous 'eye for an eye'. Even though it is (thankfully) no longer part of legal systems, the idea of revenge has not been lost. The most famous of these laws is number 196: 'If a man has knocked out the eye of another man, his eye shall be knocked out.' Even though Gandhi cleverly pointed that if this law would render everyone blind, the philosophy behind it is still active today. After all, if the boy next to you takes your lunch, wouldn't your first instinct be to grab his?

The basis of Western laws - Justinian Code

In 395, the massive Roman Empire was divided into the East and the West. Emperor Justinian was the emperor of the Eastern Roman (or Byzantium) Empire in the middle of the 5th century AD.

In 534, he ordered the creation of an imperial code: Corpus Iuris Civilis, known otherwise as the Justinian Code. By this time, the Western Roman Empire was in a steep decline, and Justinian saw it as an opportunity to put the Roman Empire back together. Although he was only partially successful, his laws still became widely used.

When Western Europe fell into the Dark Ages, the laws were mostly lost. Around the high middle ages, scholars starting looking back to the classics for inspiration, and Roman laws began to gradually reappear. Today most of the legal systems of continental Europe use the Justinian Code as a basis. It is therefore pretty easy to spot some similarities in modern law.

For instance, take this law in the Justinian Code: 'Proof is incumbent upon the party who affirms a fact, not upon him who denies it.'

Imagine you are the person being accused of stealing. Instead of the person who is accusing you of theft having to prove what you did, imagine if you had to prove that you were innocent. You would have to eliminate almost every single other possibility of what could have happened with evidence.

This law makes it the responsibility of the person who lays the charges to find the evidence, generally referred to as the burden of proof.

Right to jury and trial - Magna Carta

In England before 1215, kings ruled and applied justice using 'force and will'. This meant that the king could do whatever he wanted and exact 'justice' any way he chose. To keep the nobles obedient, the king would often use vindictive methods. This made the nobles very angry, and they decided to issue a set of written laws to keep the king from making things up.

The most immediate effect of these laws was that they made the king subject to the law. For instance, it states that a king was not allowed to levy a tax without the consent of Parliament. If the king disregarded the rights of his subjects, they now had to right to dispose of him. To date, it is the most direct questioning of a king's power.

King John of England was pressured into signing the Magna Carta, or Great Charter, in 1215, and although there have been countless amendments since then, some of the rights granted in the original document remain. It is often cited as the first step towards a British constitution.

One of the laws that has had a profound and long effect was clause 39. Clause 39 gave people the right to a trial and jury before conviction. Eventually, this became known as 'due process'. Due process was also incorporated into the United States Constitution in the 14th Amendment. It is not currently in contemporary British law, but there are two similar clauses that cover its meaning.

The significance of the Magna Carta is undeniable and can be found in many legal systems that have been influenced by the English system.

Equality - Yassa Code

Genghis Khan was not born the type of man he was going to be. His family were outcasts, his childhood was spent surrounded by tribal violence, and he had no formal education. He was a man who started at the lowest possible stair and went higher than anyone before him. Genghis created the largest empire in history - from the East China Sea, north to Russia, south to Indonesia and west through the Middle East - by using an army of only about 100,000 warriors.

The legacy of the Mongol Empire lies not in its writing or its music, but in the connections it built. By financing Christian churches in China, Buddhist temples in Persia and Muslim Koranic schools in Russia, he and his descendants transferred culture like a bee does pollen.

One of the ways Genghis united his empire was by writing the Yassa Code. No copy of it exists today, but much of the Yassa Code exists in other forms. For instance, in modern Mongolian and Turkish, variants of the word Yassa (Yoso in Mongolian and Yasa in Turkish) still mean law. There are records of Genghis' changes and legacy that make it possible to say they were the result of the Yassa Code. His decree put it into force in 1190, seeking to unite the nation by instilling understanding, tolerance and peaceful co-existence.

Although Genghis himself couldn't read, there were extremely ambitious plans to create primary schools to make the population more literate. He also made religious freedom law and disregarded the feudal system. He introduced a system where talent and action mattered more than social status. This fondness for equality translated into law: kings and commoners were held accountable under the same legal system, effectively pioneering the first time everyone was equal before the law.