This key event in Sigilian history has its roots in the kriegstanz, the long cold war that has marked the factions since their beginnings. This undercurrent of ill will amongst the factions was not always the low simmer it was today; once, centuries ago, it was an outright boil. Battles in the streets between the numerous factions (between 49 and 52 by various counts) were common, resulting in threats to the citizens regardless of faction alignment. There looked to be no end in sight to the bloodshed and terror, and Sigil was rapidly losing its place as a crossroads of the planes as more and more people thought it too risky to visit.
However, one day approximately 630 years ago, the Lady of Pain interceded. Appearing before each factol with a single dabus, she issued a now-famous pronouncement in a rare direct action, one which would ensure an end to the battles on the streets.
For a brief period, the disorder was even worse, as factions scrambled to be one of the last remaining. Some factions merged, others left Sigil, others simply dissolved or were killed off. Overall, 17,734 are recorded to have died in the faction purge due to the chaos of events. But within two weeks, indeed there were only 15 factions in the city and, most fearing that this is a now-standing rule rather than a single proclamation, none have ever tried to bring the number above this point since, with new factions only allowed to take position in the city when an existing faction disbands, dissolves, or leaves.
- Factol's Manifesto, pg.81