In almost every culture around the world, dragons have made an appearance in myths and legends. Many of these myths are similar, even though the people who created them never met.

Other strange creatures have been created by myths, but none quite as unique as dragons. Although people quickly stopped believing in other mythical animals, dragons existed in mythology for a much longer period of time. Different people have different theories of why so many cultures developed such a long lasting belief in dragons, but none can actually be proven.

Before anyone can take a guess as to why societies that never met believed in the same thing, they have to learn how closely the myths connect. From European monsters to Oriental guardians, dragons have fallen into many different categories but they have basically kept the same image. Throughout many cultures dragons may have appeared different but they have always retained the same basic core elements.

When most people think of dragons they generally think of fire breathing monsters, but originally dragons were usually connected with water. Historians use this conection with water to distinguish dragons from other mythical animals. This connection with water can be traced back to what is commonly thought to be the first dragon in mythology, the monster of watery chaos in sumerian mythology. In sumerian mythology Zu steals the laws of the universe from the Sumerians most important god Enlil. Enlil orders Ninurta, the sun god, to kill Zu and retrieve the laws, after Zu is dead order is returned to the universe. After this point in history many different cultures began to adopt the idea of gods fighting with dragons to restore order.

A Babylonian myth of creation reflects this idea in which the sea goddess Tiamat leads an army of dragons and sea serpents against the gods. The champion of the babylonian gods Marduk cuts Tiamat in half and uses one half to make the sea and the other to make the sky. Sumerian and Babylonian myths most likely had an effect on Egypt and the creation of Apophis the giant serpent who battles with the Egyptian sun god. This shows a great resemblance to Zu in Sumerian mythology. The Egyptian people believed that when the sun set it was battling with Apophis and when it rose again Apophis had been defeated and that this happened every night. It was also thought at this time that earthquakes were caused by battles between dragons and gods. Egyptians changed dragons from characters in creation myths to daily battles between good and evil. Later in Egypt dragons were associated with Seth, the violent god of destruction, who shook the very sea itself.

It was thought that after death souls of the wicked would be devoured by a fire breathing dragon. This is perhaps the first dragon to breathe fire in any culture. In the earliest writings of the old testament the storm god Yahweh is depicted destroying dragons. The dragons became a common symbol for later Hebrew prophits as enemies of Israel.

In early christian texts, dragons were depicted as the devil or the devil's servant and is generally used as a symbol for evil. In the book of Revelation, Satan is depicted as a dragon: "...and the great dragon was thrown down, that ancient serpent who is called the devil and Satan, the deceiver of the whole world..." After Satan is depicted as a dragon in the book of Revelation, the Catholic church began to use dragons as a general symbol of evil in paintings and statues.

Later in Europe these dragons in art forms were thought to be real life animals rather than symbols of evil. It was even thought that a bishop couldn't achieve sainthood without slaying a dragon. Christianity wasn't the only religion to change the myth of dragons. A new aspect was introduced to the general dragon myth by the Greeks: the idea of sacrificial virgins.

This new idea first appeared in the story of Perseus and Andromeda in which Andromeda, an Ethiopian princess, is sacrificed to a sea dragon. In the story Perseus sees Andromeda, falls instantly in love with her, and rescues her from the dragon gaining her hand in marriage. This becomes a traditional concept in almost all European dragon myths.

The greeks also introduce the idea of dragons guarding hoards of treasure. This comes from the greek author Artemidorus who believed dreams of dragons symbolized future wealth and riches, "because dragons make their fixed abode over treasures."