Archfey
Ancient entities of the Feywild, the archfey are archetypal manifestations of potent faerie power. Usually known solely by their titles, the archfey are to the Feywild what the gods are to the natural world - its architects and the prime movers thereof. Though the fey do not worship the archfey exactly, they do serve them as vassals serve their lieges. Indeed, each of the Sidhe Courts of the Feywild has one or more of the archfey as overlords. The archfey consider the gods to be rivals for power, though they do not actively consider them enemies, generally speaking.
The Unseelie
In the language of the Feywild, those who are aligned with the Archfey are referred to as "seelie", a term meaning "loyal". There are also unaligned entities, who are considered not-seelie. But there is a third classification among those who inhabit the lands of faerie: the unseelie.
The unseelie are those who are opposed to the rule of the Archfey in every way. These may be personal, political or even philosophical - there are as many reasons to oppose the rule of the Archfey as there are members of the unseelie. Most seelie believe the unseelie defy and hate the Archfey because they are wicked consorters with powers from beyond the Feywild. Traditional tales describe the unseelie as having truck with terrible shadows from the Shadowfell, or with the powers of the Primordials.
They are considered rebels, not just against the political structures of the lands of the Feywild, but against the very natural order, for they oppose the notion that the Archfey are deserving of service and emulation as beings in whom the very essence of the Feywild is concentrated and made manifest.
The unseelie serve as an all-around bogeyman and conspiracy theory - they are monster and political insurgent both. Most seelie believe that the unseelie form themselves into "courts" as well, pledging allegiance not to the service of an Archfey, but to its destruction. In truth, while the unseelie do use the term "courts" to describe their organizations, they are not mimicries of the sidhe courts. Instead, they are like cells of revolutionaries or assassins, carefully guarding the identities of their fellows from exposure.