Founded by Walter Gropius in 1919, the Bauhaus was the most influential art school of the 20th century. Its core philosophy was 'Gesamtkunstwerk'—a total work of art in which all arts, including architecture, furniture design, and typography, would eventually be brought together. The Bauhaus promoted the idea that 'form follows function,' favoring clean lines, geometric shapes, and industrial materials over ornate decoration. Though the school was forced to close by the Nazis in 1933, its teachers (like Kandinsky and Klee) fled across the globe, spreading the 'International Style' that defines modern cities today. Everything from IKEA furniture to the design of the iPhone can trace its roots back to the Bauhaus.