The Tuatha is one of the nine empires vying for the control over Countermay
Ixhasa may be the oldest civilization, but the oldest people—if you can call them that—are undoubtedly the Tuatha. Hailing from beyond the Veil in the Mirror World that lies parallel to Countermay, the Tuatha are not a homogenous group but a collection of the ageless fae—fairies in the vulgar tongue—noble and cruel, beautiful and monstrous. Powered by their glamours and ability to slip beyond the Veil at will, the curious and mischievous Tuatha visited Countermay for their own purposes and found a life in local legend.
It wasn’t until the Collapse of the Veil, with their ability to vanish lost, that the Tuatha found themselves forced to interact with the other empires and form a state. Though the Veil has since been restored, the trade and diplomatic bonds the Tuatha formed in the interim have had an indelible impact on their culture, one that escalated a longstanding internal schism into a full-blown civil war.
The Seelie—the noble Sidhe and nymphs, helpful brownies and the like—found the mortal empires and their frailties and potential fascinating, and advocated for ongoing interaction with them. But their opponents, the Unseelie—the dark elves, the ravenous goblins, treacherous changelings and hags—saw weak peoples fit only for exploitation and enslavement. During the War of the God-King, Tuatha Dundareel helped Simm Buxtahude to forge an alliance to prevent The Cult of Shad-Hujem from reaching The God Head Seat. A prince of the Seelie Tuatha, Dundareel committed his forces to help trick the God-King into committing his own. Believing the innate magic of the Seelie would protect them from the effects of The Displaced's bomb, the Seelie made up the majority of the force used to draw in the Hujem.
While the bomb was successful in killing Shad-Hujem and breaking his army, it had unexpected effects on many of the Seelie. While some like Dundareel were able to recover from the radiation poisoning, many more perished after a long wasting sickness. This gave the Unseelie Tuatha the advantage they needed to overthrow the Seelie, killing many members of the royal family, except Dundareel, who managed to escape using his magic. The resulting war was fought on both sides of the Veil. In the end, the Unseelie triumphed. They exiled the princes of the Sidhe to Countermay. The Tuatha today are an unstable and unpredictable foe, chaotic and mercurial and honestly best avoided.