World War I had a significant effect on European politics and economics, especially in Russia, which became the world’s first Communist nation in 1917 when a popular revolution brought the Bolshevik ("Majority") Communist party of Vladimir Lenin to power.  The Soviet Union, a Communist state encompassing Russia and neighboring areas, was created in 1922.

     The U.S. emerged from the war as the economic leaders of the West, and economic recovery followed in Western Europe, but the 1929 New York stock market crash plunged the world into the Great Depression.  During the 1930s the U.S., Britain, and France instituted state welfare policies to provide jobs and stimulate their economies.  However, elsewhere in Europe, the economic crisis brought to power right-wing totalitarian regimes: Mussolini had already become the fascist dictator of Italy in the mid-20s; he was followed in Germany in 1933 by the Nazi leader Hitler and in Spain in 1939 by General Franco.  In the Soviet Union, Joseph Stalin (who had succeeded Lenin in 1924) consolidated his authoritarian rule through the execution or imprisonment of millions of his political opponents.

     German aggression led in 1939 to the outbreak of World War II, which initially pitted Germany, Italy, Jqapan, and the Soviet Union against Britain and France.  The Soviet Union turned against Germany in 1941, and later that year the U.S. was drawn into the war by the Japanese attack on the U.S. naval base at Pearl Harbor, in Hawaii.  World War II claimed the lives of between 15 and 20 million soldiers and approximately 25 million civilians, including 6 million European Jews who perished in the Nazi Holocaust.  It ended first in Europe in May 1945, then in the Pacific in August 1945 when the U.S. dropped atomic bombs on Hiroshima and Nagasaki, Japan, ushering in the nuclear era, with its constant threat of global annihilation.

    During the two world wars, technological innovations resulted in such deadly devices as the army tank, the fighter bomber, and the atomic bomb.  Yet dramatic scientific developments and improvements transformed life in times of peace; more effective medicines; agricultural improvements; communications breakthroughs with the radio, wireless telegraph, radar, television, and motion picture; and transportation inventions, the automobile and airplane.  The first analog and digital computers were introduced in the 1930s.

     Revolutionary developments in art and culture accompanied the momentous changes in politics, economics, and science.  Historians have gathered these developments under the label of modernism.  Modernism simply means "up-to-date", but the term modernism connotes a rejection of conventions and a commitment to radical innovation; animating modernism is the desire to "make it new" (in the words of poet Ezra Pound).  Like scientists and inventors, modernist artists engage in a process of experimentation and discovery, seeking to explore new possibilities of creativity and expression in a rapidly changing world.

     After 1900 the pace of artist innovation increased in a succession of movements, or "isms", including Fauvism, Expressionism, Cubism, Futurism, Dadaism, Suprematism, Constructivism, Purism, Neoplasticism, and Surrealism.  Each was led by charismatic artists who promoted their movements unique philosophies through written statements, some of which took the form of manifestos.  Although modernism is characterized by tremendous aesthetic diversity, several broad tendencies mark many modern artists.  Foremost is a tendency toward abstraction.  While some modernists presented recognizable subject matter in a distorted manner, others created completely abstract, or nonrepresentational, art, which communicates exclusively through such formal means as line, shape, space, color, and texture.  A second feature of modernism is a tendency to emphasize physical processes through visible brushstrokes and chisel marks, for example, and the materials used.  A third feature is modernism’s continual questioning of the nature of art itself through the adoptoin of new techniques and materials, including ordinary, “nonartistic” materials that break down distinctions between art and everyday life.

     The rise of European and American modernism in the early twentieth century was driven by such exhibitions as the 1905 Salon d’Automne (“Autumn Salon”) in Paris, which launched the Fauve movement; the first exhibition of Der Blaue Reiter group in Munich in 1911; and the 1913 New York Armory Show,the first large-scale introduction of European modernism to American audiences.  A key event in the shaping of the modernist canon was the 1929 opening of the Museum of Modern Art in New York, which rapidly assembled the world’s finest modernist collection.  State-supported museums dedicated to modern art also opened in other capitals, such as Paris, Rome, Brussels, and Madrid, signaling the transformation of modernism from an embattled fringe movement to officially recognized “high culture”.