 The boom lasted until November 11, 1919, when the infamous Centralia Massacre occurred.Spurred on by local lumber barons, American Legionnaires (many of whom had returned from WWI to find their jobs filled by pro-union members of the Industrial Workers of the World (IWW)), used the Armistice Day parade to attack the IWW hall.Marching with loaded weapons, the Legionnaires broke from the parade and stormed the hall in an effort to bust union organizing efforts by what was seen to be a Bolshevik-inspired labor movement.