Dada was an anti-war art movement that began in 1916 in Zurich during World War I. Artists from both sides of the war fled to neutral Zurich. The movement was founded by Hugo Ball who opened the Cabaret Voltaire nightclub. Key figures included Tristan Tzara, Francis Picabia, Hans Richter, Jean Arp, Marcel Duchamp, and Man Ray. Dada rejected logic and reason and incorporated chance procedures. Notable works included Duchamp's "Fountain" and readymades, and Man Ray's photograms. Dada used nonsensical language and imagery to oppose militarism and nationalism which they blamed for war.