The German artist Wassily Kandinsky (1866-1944) is considered to be the first entirely abstract artist. Prior to World War II, Kandinsky was part of the Expressionist group Der Blaue Reiter and later he taught at the Bauhaus. His Improvisations are a series of paintings which consist of brightly colored abstract shapes which allude to the impact of the moving quality of music on his life. Kandinsky's main interest was creating expressist art with the pure elements: color and shape. In "Kandinsky: Complete Writings on Art," Kandinsky writes about the influence of science in his art: "A scientific event removed one of the most important obstacles from my path. This was the further collapse of the atom". This discovery helped him to question his preconceived ideas about the world and his art.
Encyclopaedia Britannica: Kandinsky (Princeton and subscribers only) WebMuseum: Kandinsky Sloth's Kandinsky page: About a dozen paintings and a brief biography.