In 1919, the United States was experiencing its first "Red Scare." Following the Bolshevik Revolution in Russia in 1917, public sentiment against Socialists - who maintained a strong presence in Cleveland during this era - was high. Many viewed the Socialists and their sympathizers as a threat to American society.
The 1919 Cleveland May Day Riot began when a World War I veteran took offense at the red flags being proudly waved by Socialist demonstrators as they marched toward Public Square. A fight broke out, and soon enough a melee between Socialist and anti-Socialist citizens ensued. The violence was only quelled after the intervention of police and military units. At one point during the widespread rioting, a mob stormed and ransacked the Socialist Party headquarters on Prospect Avenue. The riots injured dozens and resulted in two deaths. The event highlighted the simmering tensions that existed in Cleveland after World War I.
This tension would continue well into the 1930s when unionists, leftists, and unemployed workers joined together in a series of strikes and protests under the banner of the Unemployed Council. Although Communist and Socialist movements in the US have waned since World War II, Public Square continues to serve as a setting for protests of all types.