Much of their early history is lost, but fragments of ancient history are still known to some on Erdreja. Legend has it that the Lios were instrumental in creating the Were-Kin. They certainly tend to have a great affinity for such creatures and also find followers amongst races such as the pixies, sprites, goblins and such like.
In the Younger days, the humans, led astray by the Mordred, made war against the Elder races, led by the Pendragon. The war went badly for the elder races, who struggled to find a way to deal with the new form of magic, Spellcasting, which humans unleashed upon them. As the tide was turning, however, the Mordred created a device to age the elder races and thus kill them. The device was powered by Incantor magic, and though the Lios tried, they were unable to destroy the device.
Faced with a difficult choice between death and the loss of a substantial part of their tradition and powers, the Lios bound Incantation magic out of the world in order to destroy the devices' source of power. The war ended in a stalemate, and though many of the elder races chose to remain in numbers, living in an uneasy peace with the humans, the Lios withdrew to Ynys Glas and remained there for many centuries.
Ages later, around 1095AF, Incantation magic began to break through the pattern which the Lios had woven to keep it away. As the pattern broke down further ties to the ancestors strengthened and more Incantation magic returned. But the device became stronger too, and the elder races began to age and die once more.
Rather than bind it out of the world once more, the Queen and Chamberlain, accompanied by the Grey Council, attended the Gathering of 1095AF, and asked for the aid of the factions in destroying the device once and for all, so that Incantation magic could be fully returned. Mostly, the factions co-operated - the Tarantulas being the notable exception - and the device was destroyed.
Since then the Lios have intermittently returned to Erdreja and some - Gwydion, Cerridwen, Morrigan and Blodwyn, along with their followers now call Albion home.