Ever since the Dawn of Time

Ever since the dawn of ages, people have been judged, hunted, hurt. Men have always started wars or battles in order to place their laws over everyone elses. During those time, the first witches and wizards appeared. They offered their services to the side they thought was right, but when time came that their magic was no more of need, the people chased them down, killing them, masacrering them only because they feared those men and women. They feared their strange ways. That's how humans faced their fears, they got rid of them.
The hunt gave new ways to the magic based people. They changed, slowly but surely. Some concentrated on becoming healers, praised by the people they help. Others fed the poor by hunting for them in their animal transformation forms. But others wanted the normal humans to know they were weak and parhetic compared to them and praticed the darkest arts.
It didn't mattered what they did, wether they helped or not, when the humans knew of their existence they were hunted, chased away from population. In order to keep the magy safe, five great wizards and witches created a portal to a world between two worlds. And there, they built an academy worthy to teach the young generation to use their gifts in safety. They wrote everything they knew in the old language and then left the world with one spell: when the Magy children reach the age of Sixteen, the spell will anovoidably lead them to the academy.