The Order of the Black Hand was founded by Arch Primarch Idamar II of the Temple of Man Supreme in the second century of Enlightenment to combat heresy, divine worship and witchcraft. In the centuries that has passed since then, all rivalling creeds and beliefs have been persecuted with ruthless and methodical efficiency by the Sensors of the order. Witches and warlocks have been driven out or killed, and thousands of dissidents have been convicted and their souls purified. The turning point of the Manus Nigrum came in the early sixth century, when the infamous Cardinal Ambrosius was appointed High Sensor of the order. Under his administration the web of secrecy that now cover the Black Hand was woven. He also instated the Seven Doctrines that even to this day strikes fear in any who comes face to face with a Sensor. Of the Seven Doctrines, only three are known by name: that of the Black Mark, that of the Purification of the Soul, and that of the Forfeiture of the Soul. When someone is marked with the Black Mark, anyone who has liaisons with him is considered Tainted. Further, it is the sacred duty of all Humanists to slay him if they can.
The Purification of the Soul is a complex ritual of torture employed to remove the Taint from a soul so that it doesn't corrupt Creation when it passes on. Those so purified dies a good death, or so the Perfecti claim. The last of the known Doctrines, that of the Forfeiture of the Soul is the most feared instrument of the Hand; if a soul is too corrupted to purify, it will be stripped from its bearer and burned. Those unfortunates who are thus treated are then freed and left to wander, so that others are reminded to stay pure, until their lonesome, soulless body finally dies. Laying hand on the Forfeited is prohibited by law. In the years following the instatement of the Seven Doctrines, the order grew too powerful for the Arch Primarch to control, and now its Sensors operate with impunity in the Humanist realms. In the past, Cardinals and Kings, as well as two Arch Primarchs have been apprehended and killed by the Black Hand. It is no wonder then, that the mere mentioning of the order will cause even the most pious and steadfast to cast a nervous glance over their shoulder. Little is known .about the organisation of the Manus Nigrum, as all its members title themselves Sensor when addressing outsiders. Rumours have it that there are seven tiers of the order, and there are, according to whom you are speaking with, seven, five, or three Cardinals at the highest tier. Some even whisper that the ghost of Cardinal Ambrosius still controls the Black Hand of Man. The latter is, of course, an outlandish notion, mostly fit to scare idiots and little children. Over the last generation, following the Sundering, all Erian realms have seen an upsurge in heresies, witches's covens, blasphemous worship, and a spreading of subversive rumours and ideas. In Southern Eria, the Manus Nigrum has reacted with remorseless and vigilant determination, culling insurgencies and rooting out occultists and idolators with vigour and conviction. Never before in the history of man has the book pyres and the Pogroms been more widespread, setting aside earthly laws and privileges alike.