Darkness is a symbol of evil or mystery or fear. The darkness is almost a monster waiting to swallow you whole. It is the absence of light. Scientifically it is only possible to have a reduced amount of light. The emotional response to an absence of light has inspired metaphor in literature, symbolism in art, and emphasis. The story of the Light versus the Darkness is one that everyone thinks that they know. The Light is good and the Dark is bad. However, this is too broad of a generalization, for not all of those who follow the Light can be considered to be "good," and many good people do indeed follow the Dark—you may even know a few yourself.
Underneath all of the issues the Light and the Dark are very simple. It simply has to do with one's personal point of view. A person who sees the world as a bad place, who sees nothing good anywhere he or she turns, and who thinks that there is no hope of anything better is someone who has a "dark" mind. These people are not necessarily followers of the Dark, but they ARE the basis of that particular orientation. On the other hand, a person who has a positive outlook on life, who tries to find the good in everything, and who often tries to point out that the world is not as bad as people think is a person who is of the Light. Neither one of these ways of thinking is necessarily right or wrong, and both can make good arguments for their own point of view, which is where, ultimately, the problem lies.
Over the years, all of the wars and conflicts that have taken place for anything other than land disputes have been somehow in the form of Light against Dark (in the universe of Firefly Cross, not necessarily always true in our own history). People who had extreme opinions on either side would spark up problems. Once the problems had begun, other people who would normally have been more in the middle, would choose one side or the other based on their opinions at that time, and wars would develop. This is how the whole problem began. The designations of "Light" and "Dark" began to be used to differentiate between the two sides, for "good and evil" were not appropriate since neither side was good and neither side was evil. For it is true that too much light can do as much or more harm than too much darkness, and wherever you find one, the other must surely exist. They are exact opposites, but there will never be one without the other, they must balance each other.
As a quick explination of these two sides as they related to the different conflitcs that arose:
Dark: Followers of the Dark with be those with very pessimistic attitudes. They find fault with everything in the world, and humans are one of the greatest sources of those faults. They like to use creatures that aren't human and can be easily controlled, giving anyone too much freedom is a recipe for disaster in their eyes. The negative aspect of the Dark's view is that nothing positive can ever come from it, there are always more and more problems to solve, the world is never a good enough place for them. A leader of the Dark may try to conquer the world in order to force his view on how things should be done upon the people, in other words conquer in the name of an idea. (Such as Hitler and the Nazis attempted—there were many people who saw them as heros, and as the Christians acted in the Crusades.)
After Fate took control of these conflicts, they started to be more organized and simple. With the power that Fate had given to each side, there were fewer people just "in the middle." Everyone chose one side or another to be behind this power. There were fewer "innocents" in the struggles. As the power on each side began to grow, creatures of magic began to appear that were created by and would supplement the power of each side. For the Light, the creatures that were created included the likes of unicorns, nymphs, and dryads. Darklings were creatures such as vampires and werewolves. After a time, it became possible to gauge the power of the Light and the Dark based on how many of these creatures existed.
It so happened that after Fate took over, the Light began to win almost every battle against the Dark. This was due mainly to the Dark's negative outlook, they were constantly underestimating the Light, while the Light's positive outlook gave them confidence in every battle. This is when the concepts of Dark and Light as evil and good began to emerge. People thought that the "good" would always triumph. Even so, this angered the agents of the Dark, and eventually pushed them to take actions which concluded with the control of the battle outside of Fate's total control. (see the page on the history in order to get this in more detail. This is where the two pages begin to cross information.)
Once Fate began to lose control, everything began to change. All the centuries of control after the initial chaos broke down, and the conflicts became more chaotic than they had ever been. Since Fate's control still had some influence over the Dark, she was able to hold them together fairly well, but the Light began to fall apart, and when a foolish keeper was chosen, the Light was finally defeated...and it was to remain defeated from that day on.
In the present time of Firefly Cross, the Dark has ruled from more than a thousand years, and their power has only grown in all that time. The people of this world are very cynical, and cannot seem to see the good in anything. The Light has become nearly non-existent. All of the creatures of the Light, Unicorns and such, have long since gone extinct, and all that remains of the Light's power is Chaerius (the dragon), Ra'yl (the guardian), and the sword, Ra'grathon. Fate has charged these few and their new keeper, Kanye West, with an important task. Their role is not to be victorious, for the Light does not have enough power for that to be possible, but they are to try to bring the conflict back under Fate's control. They are to stop the Dark and reduce their power to that of the Light, so that it all may begin again.