Let the blood of the traitors flow. That is the only way to save the country.
- -Jean-Paul Marat
Early in September of 1792, as Prussia began its invasion of revolting France, accusations emerged of a plot of assassination against "all good citizens" between the 2nd and 7th of the month. Thus, on the 2nd, political and non-political prisoners were rounded up by "assassins" (later known as the Septembriseurs) and sent to an informal trial where they were judged and then quickly and savagely executed. Half of the entire prison population of Paris were killed (some 1,200 souls) over five days. Many were priests and royalists but most were normal prisoners with no political ties.
It's hard to overstate the horrifying nature of the bloodshed. Bodies were mutilated and desecrated for pure enjoyment. Women wore ears as trophies. People watched the slaying like it was a sport. There are even reports that men drank blood actually squeezed out of the hearts of aristocrats.
Most Carthians wave off the massacres as mistakes every ideology makes but some see them as a valuable model for the affairs of Kindred. These vampires recognize their world is different from mortals'. Their kings do not simply died and elders are far less flexible than the most conservative of kine. In the Requiem, progress requires bloodshed. Let's make sure it's the bad guys who are bleeding.
Septembriseurs take particular note in the incident of Frenchmen actually drinking aristocratic blood. Its similarities of Diablerie are unsettlingly close and most cite this as proof that the Septembriseurs had a few Kindred in their ranks. Septembriseurs take this as a sign that drinking the heart's blood is a neccessary step in establishing a new and free order. As a matter of principle, however, they limit the act to the Prince and his privledged supporters. Sadly, "privledged" and "supporters" are relative terms when the euphoria of violence surfaces.
The Septembriseurs are known for emulating many of the practices of the French revolutions. The accused would go to trial where their guilt was demonstrated to the people. Their murders are often brutal and savage. Torture is common, as is using a loved one to coax out a traitor. The Septembriseurs claim this is the only way to strike genuine fear in the hearts of the enemies of freedom.
Septembriseurs are a minor but dangerous faction in the Requiem. In every city where a non-Catharian rules, they support the violent overthrow of the Prince. Even some Carthian rules have been marked as traitors to the Cause. What "the Cause" is differs from member to member, but themes of "freedom" and "opportunity" run common to them all.
They are not stupid, however. Most Septembriseurs won't admit to being so. Instead they try to instigate violent retaliation in the Kindred population. When they succeed they take the helm of the Moment so they can oversee its accomplishment and drink the blood of the Prince. When they fail, they quietly leave to the next city, hoping to find a new garden to tend the cause. One by one, they hope to turn Kindred cities into havens for the Cathrian Movement.
Few "revolutions" succeed even after the day is won. The vast majority of Septembriseurs simply leave when the violence subsides, relying on the locals to rebuild the government. On the few ocasions a Septembriseur stays, the outcome is usually worse than their predecesor's rule. Torture and assassinations are common because violence tends to be the only language he speaks. Most Septembriseurs have learned they are far better suited for revolutions than ruling.