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Before the Armory Show of 1913, American painters believed Cubism to be the most avant-garde Modern Art movement. Cubism was a revolutionary art movement pioneered by artists like Pablo Picasso and Georges Braque. It focused on depicting objects from multiple perspectives and breaking them down into geometric shapes.
American painters admired Cubism for its innovative approach to representing the world in a non-traditional way. They saw it as a bold departure from traditional artistic conventions and a movement that challenged perceptions of reality and form in art.
French Impressionism, German Expressionism, and Fauvism were also influential Modern Art movements, but it was Cubism that captured the attention of American painters as the most cutting-edge and avant-garde movement before the Armory Show of 1913.