Organized by the Communist International, hundreds of thousands of people in major cities around the world marched to protest mass unemployment associated with the Great Depression.

The Communist International, abbreviated as Comintern and also known as the Third International, was a political international which existed from 1919 to 1943 and advocated world communism. Emerging from the collapse of the Second International during World War I, the Comintern was founded in March 1919 at a congress in Moscow convened by Vladimir Lenin and the Russian Communist Party (Bolsheviks) (RCP), which aimed to create a new international body committed to revolutionary socialism and the overthrow of capitalism worldwide.

International Unemployment Day was a coordinated international campaign of marches and demonstrations, marked by hundreds of thousands of people in major cities around the world taking to the streets to protest mass unemployment associated with the Great Depression. The Unemployment Day marches, organized by the Communist International and coordinated by its various member parties, resulted in two deaths of protestors in Berlin, injuries at events in Vienna and the Basque city of Bilbao, and less violent outcomes in London and Sydney.

The Great Depression was a severe global economic downturn from 1929 to 1939. The period was characterized by high rates of unemployment and poverty, drastic reductions in industrial production and international trade, and widespread bank and business failures around the world. The economic contagion began in 1929 in the United States, the largest economy in the world, with the devastating Wall Street crash of 1929 often considered the beginning of the Depression. Among the countries with the most unemployed were the U.S., the United Kingdom, and Germany.