The Circle of Eighteen was a group of sorcerers who led the immense Rebel armies against The Lady's Empire up to and during the Battle of Charm. In addition to their massive military campaigns, the Circle used considerable resources to locate the child who was prophesied to be the reincarnation of the White Rose. Their search intensified as the comet grew larger in the sky but was never successful.
Far from being a force for good and justice, the Circle was known to use brutal tactics, and many of its most important members were evil. Soulcatcher considered them to be hypocrites. More significantly, the Lady knew many of them were not striving to independently overthrow her Imperial rule to establish fair government, but were rather pawns of the Dominator, who was influencing them from deep within his enchanted, subterranean prison in the Barrowland. In the wider context, the Circle was simply the first of several attempts by the Dominator to escape captivity.
Several members of the Circle were killed before the climactic Battle of Charm, most prominently: Raker, Harden, Moth, Sidle, Linger, and Parcel. And three of them were kidnapped and enslaved to be the first of the New Taken: Whisper, Feather, and Journey. The Lady confirmed that the remaining members of the Circle were all killed during the Battle of Charm, before the fighting was even finished; by the end of that battle, their armies were utterly defeated as well.
The Rebel movement would outlive the Circle. The Black Company itself would later become the backbone of the next Rebel movement. Under Darling's leadership, the new Rebel would have an entirely different unifying spirit than it had during the years of the Circle.
Most of the Circle were never encountered by Croaker, and seven of the original eighteen were not even mentioned by name in his chronicles. Also, the Circle replenished its ranks at least twice, to fill the openings left by two deaths among its members. Those whose names made it to Croaker's annals are, in order of mention: