The history of modern architecture shows the personality of the architect who designed it. This style began in the United States and Europe. It then spread from there to the rest of the world. Modern architects reacted against the architecture of the 19th century; they thought it borrowed too many ideas from the past. As the 20th century began they believed it was necessary to invent an architecture that expressed the spirit of a new age and would surpass the styles, materials, and technologies of earlier architecture. New materials that were introduced were glass, steel, and concrete. The Crystal P