Disclaimer: Honestly I feel no need for these. Common sense really.
The beginning of the Dark Arts can be traced back to Morgan le Fay. Some historians will debate that it was the Ancient Egyptians that started this noble art, but I must disagree with them. The Egyptian rulers were too focused on escaping death to have their magicians truly delve into the Dark Arts. No, I would rather call it Black Arts, than Dark. The true Dark Arts began when Morgan, in her hate and jealousy of Merlin and Arthur's wife Guinevere, realized the power our emotions have over magic. However Morgan let her emotions conquer her and she became lost in the power the Dark Arts give.
I remember a day I was arguing with Godric over how the Dark Arts is all magic that uses our emotions; such as love, hate, lust, and anger. I pointed out the Patronus Charm, which is produced from happiness and our feelings of joy, is actually a form of Dark Arts. In his anger he set his blasted bird on me and the Hall erupted in laughter. I'm afraid that started the persecution of me and I left Hogwarts to further my studies in peace.
However that peace didn't last for long. A great malady befell my family and in my rage I became lost in the Dark. I still have some moments of clarity but I know soon I will be lost to the same magic I loved when I was younger. My family split years ago and I am left with my youngest child. He is such a sweet thing, looking after his crazy father. I have left him with all the knowledge I gained in studying my noble art with advice I should have heeded years ago. With a heart that is Always Pure, can one master the Dark. He has promised to separate himself from the family, and to start a new life away from this madness.
Tears fall from my eyes as I watch him leave. The Dark calls to me and I have little will left to resist. Alone, I say my last goodbyes to my last son, Corvus Black.
In the Hand of Salzar Slytherin
An excerpt from The Ways of the Dark