From the Encyclopedia of Cleveland
The MAY DAY RIOTS, which occurred in Cleveland on 1 May (May Day) 1919, involved Socialists, trade-union members, police, and military troops. The Socialists and trade unionists were participants in a May Day parade to protest the recent jailing of Socialist leader Eugene Debs and to promote the mayoral candidacy of its organizer, CHAS. RUTHENBERG†. Its 32 labor and Socialist groups were divided into 4 units, each with a red flag and an American flag at its head; many marchers also wore red clothing or red badges. While marching to PUBLIC SQUARE one of the units was stopped on Superior Ave. by a group of Victory Loan Workers (see WORLD WAR I), who asked that their red flags be lowered, and at that point the rioting began. Before the day ended, the disorder had spread to Public Square and to the Socialist party headquarters on Prospect Ave., which was ransacked by a mob of 100 men. Two people were killed, 40 injured, and 116 arrested in the course of the violence, and mounted police, army trucks, and tanks were needed to restore order. Cleveland’s riots were the most violent of a series of similar disorders that took place throughout the U.S. Although it is uncertain who actually began the trouble, the actions of those involved were largely shaped by the anti-Bolshevik hysteria that permeated the country during the “Red Scare” of 1919.