Oswald Mathias Ungers (12 July 1926 – 30 September 2007) was a German architect and architectural theorist, known for his rationalist designs and the use of cubic forms. Among his notable projects are museums in Frankfurt, Hamburg and Cologne. Biography Oswald Mathias Ungers was born in Kaisersesch in the Eifel region. From 1947 to 1950 he studied architecture at the University of Karlsruhe under Egon Eiermann. He set up an architectural practice in Cologne in 1950, and opened offices in Berlin in 1964, Frankfurt in 1974 and Karlsruhe in 1983. He was a professor at the Technical University of Berlin from 1963 to 1967 and served as the dean of the faculty of architecture from 1965 to 1967. In 1968 he moved to the United States, where he became the chair of the department of architecture at Cornell University from 1969 to 1975. In 1971 he became a member of the American Institute of Architects. He was also a visiting professor at Harvard University (1973 and 1978) and the University of California, Los Angeles (1974/75). He returned to Germany in 1976, becoming a visiting professor at the University of Applied Arts Vienna (1979/80) and a full professor at the Kunstakademie Düsseldorf (1986). Oswald Mathias Ungers died on 30 September 2007 from pneumonia. He was married to Liselotte Gabler (1926–2010) and had one son (Simon Ungers) and two daughters. On his work Ungers' buildings are characterized by strict geometrical design grid. Basic design elements of his architecture are elementary forms such as square, circle or cube and sphere, which Ungers varied and transformed in his designs. As an architectural theorist and university lecturer, Ungers developed what his critics called "quadratism", his admirers "German rationalism". In doing so, he resorted to the teaching of Jean-Nicolas-Louis Durand who had published in 1820 his pattern books with geometric prototypes for "any building". In his formal language, Ungers explicitly referred to elementary architectural design elements that are independent of contemporary tastes. His historical role models in the history of architecture come mainly from Roman-Greek antiquity. His work was therefore occasionally criticized as formalistic. In connection with his construction on the Frankfurt Messe grounds, there was often talk of a "new clarity". Like hardly any other architect, Ungers has remained true to his once chosen formal language for decades. He was one of the leading theoreticians of Second Modernism. Well-known students of Ungers include Max Dudler,