See also Part IX: Black Winter , the dispute that arose during the Black Winter.
“Never before has the Black Mist spread so far into Valoran. Never have we seen a Harrowing like that of 26 CLE. But we are resolved that we will weather this dreadful storm, this black winter, and prove once more that the magic that threatened to destroy our world during the Rune Wars can be turned to her protection.” —High Councilor Vessaria Kolminye, Harrow’s End Address of 24 November, 26 CLE
The Black Winter was a sustained arcane phenomenon which arose during the Harrowing of 26 CLE. It began when the Black Mist blew through Bilgewater into the mainland, and met a blizzard from the Freljord at the site of the Institute of War. Whereas a Harrowing traditionally dissipates by mid-November, the Black Winter did not. Three member-states succeeded in overcoming the Black Winter: Noxus, Demacia, and Ionia. The other states petitioned the League to address the crisis, and a special session was called. Noxus refused to play any part in the matter, satisfied with its own solution. Demacia and Ionia had succeeded by notably different methods: Demacia by hunting down necromancers and destroying the undead, Ionia by communicating with these restless spirits and restoring balance between the worlds of the living and the dead. A League dispute arose as to which of them would lead the combined Valoranian effort.
Demacia prevailed, and Sir Honnan Laurent led the nations of Valoran in a crusade against the Black Winter. The dispute concluded on 9 January, 27 CLE.