The War of the Guilds ran from 1096 to 1354 and was one of the major events in the history of Wraith: The Oblivion. It shaped the workings of the Guilds of Stygia, as well as the resulting allies and enemies.
It began with a boast from the Artificers. The Artificers already considered themselves the first Guild to officially form (although the Pardoners and Oracles would probably have something to say about that). They were in control of one of Stygia's more lucrative and powerful businesses, soulforging. They worked closely with Charon and his government. And so, they naturally considered themselves the head of all Guilds for their superiority in age, finance, and power.
Many Guilds fumed under their condescending attitude, particularly the Masquers. Many plans and agendas of other Guilds had been twisted to suit the Artificers' needs or desires. Officially proclaiming such, however, was the straw that broke the camels back. A number of other conflicts between other Guilds came to light and squabbling turned into full-fledged fighting. For over three hundred years, battles raged across Stygia. Charon allowed them at first, hoping the Guilds would burn themselves out with pointless battles, but as it stretched over the centuries, he became very impatient. It was only thanks to the intervention of Sister Acceptance of the Pardoners that the Guilds were even continued to exist.
Finally, under threat from the Pardoners to cease their all-important services to any Guilds who continued to fight one another and not sign a treaty, thirteen Guilds came together to sign the Compact of the Guilds. Notably missing from the Compact were the Alchemists (shunned by their parent Guild the Artificers), the Solicitors (banned by Stygia due to the abuse of their Arcanos), and the Mnemoi (who had "become corrupt" and since been universally loathed). The others ceased their war, ending this turbulent chapter in Stygian history.