The Sisterhood of the Radiant Heart, were a coven of good witches who practiced white magic and who devoted themselves to protecting the world and mankind from the forces of Evil. Sheriff August Corbin indirectly mentioned them when he in his recordings talked about two covens in Sleepy Hollow, one good, the other evil. The leader of the Sisters was Katrina Crane, wife of Ichabod Crane. During the Revolutionary War, the Sisters opposed the Order of the Blood Moon, a dark coven led by Serilda of Abaddon, with Katrina herself performing the spell which made Serilda vulnerable, resulting in her capture and execution.
They would later turn against Katrina after she tempted fate by sealing Ichabod away. For this act, they deposed her as their leader and imprisoned her in Purgatory allowing The Four Who Speak As One to take control.