The War of Chicago was the name of a series of battles waged between many factions of Cainite and Garou in the city of Chicago around 1993 - an event that has been prophesied by the werewolf known as Gray Raven, in the year of 1925.
While Kindred and Garou, regardless of geographic location, had little love for each other, both societies in the area existed under a de facto truce for decades.
The real cause for the escalation of hostilities was a temporary alliance of Sabbat and Black Spiral Dancer motives: the Dancers would help the Sabbat in its crusade for control of Camarilla-held interests in Chicago, and in return the Sabbat would lend forces for an assault on the Fanum - a potent Caern within the city.
True to past methodology, Sabbat and Dancer strategies involved manipulating their enemies into heightened mistrust of the others. Eventually bloodshed broke out on a wide scale between Kindred and Garou with a Blood Hunt being called on all werewolves by then-Prince Lodin, and with Garou leadership from most, if not all Tribes, assembling massive strike forces to assault the city's vampires.
During the week of the war the Celestine Jupiter, the Totem of the Fanum, made Chicago's Umbra a reflection of its suffering making it dangerous and unpredictable manifesting a great spirit-storm that gave everything a blood-red hue. Wyrm and Weaver spirits roamed due to the Celestine's lessened vigilance and Dancer involvement, assaulting Gaian Garou who entered it.
In the end both sides had suffered many deaths, including the Cainite Prince Lodin, and the machinations of the Sabbat and Dancers were brought to light. Learning of the Sabbat plot and Dancer involvement, the Kindred and Garou agreed to a truce - as much as it was before the war. In the aftermath, Chicago's Camarilla was vastly changed due to disappearances and destruction of key members of the governing body.