Gottfried Semper (1803-1879) was a German architect, art critic, and professor of architecture, who designed and built the Semper Opera House in Dresden between 1838 and 1841. He wrote extensively about the origins of architecture, especially in his book The Four Elements of Architecture from 1851, and he was one of the major players of the controversial debates surrounding polychrome architecture of ancient Greece. Beside the Dresden opera he has designed works at any scale, from a baton for Richard Wagner to urban interventions like the re-design of the Ringstrasse in Vienna.