Le Corbusier in the context of "Proportion (architecture)"

Modern architecture, also called modernist architecture, or the modern movement, is an architectural movement and style that was prominent in the 20th century, between the earlier Art Deco and later postmodern movements. Modern architecture was based upon new and innovative technologies of construction (particularly the use of glass, steel, and concrete); the principle of functionalism (i.e. that form should follow function); an embrace of minimalism; and a rejection of ornament.

According to Le Corbusier, the roots of the movement were to be found in the works of Eugène Viollet-le-Duc, while Mies van der Rohe was heavily inspired by Karl Friedrich Schinkel. The movement emerged in the first half of the 20th century and became dominant after World War II until the 1980s, when it was gradually replaced as the principal style for institutional and corporate buildings by postmodern architecture.

The headquarters of the United Nations (UN) is on 17 to 18 acres (6.9 to 7.3 ha) of grounds in the Turtle Bay neighborhood of Midtown Manhattan in New York City. It borders First Avenue to the west, 42nd Street to the south, 48th Street to the north, and the East River to the east. Completed in 1952, the complex consists of several structures, including the Secretariat, Conference, and General Assembly buildings, and the Dag Hammarskjöld Library. The complex was designed by a board of architects led by Wallace Harrison and built by the architectural firm Harrison & Abramovitz, with final projects developed by Oscar Niemeyer and Le Corbusier. The term Turtle Bay is occasionally used as a metonym for the UN headquarters or for the United Nations as a whole.

The headquarters holds the seats of the principal organs of the UN, including the General Assembly and the Security Council, but excluding the International Court of Justice, which is seated in The Hague. The United Nations has three additional subsidiary regional headquarters or headquarters districts. These were opened in Geneva (Switzerland) in 1946, Vienna (Austria) in 1980, and Nairobi (Kenya) in 1996. These adjunct offices help represent UN interests, facilitate diplomatic activities, and enjoy certain extraterritorial privileges, but do not contain the seats of major organs.

Eugène Emmanuel Viollet-le-Duc (French: [øʒɛn vjɔlɛ lə dyk]; 27 January 1814 – 17 September 1879) was a French architect and author, famous for his restoration of the most prominent medieval landmarks in France. His major restoration projects included Notre-Dame de Paris, the Basilica of Saint Denis, Mont Saint-Michel, Sainte-Chapelle, the medieval walls of the city of Carcassonne, and Château de Roquetaillade in the Bordeaux region.

His writings on decoration and on the relationship between form and function in architecture had a fundamental influence on a whole new generation of architects, including all the major Art Nouveau artists: Antoni Gaudí, Victor Horta, Hector Guimard, Henry van de Velde, Henri Sauvage and the École de Nancy, Paul Hankar, Otto Wagner, Eugène Grasset, Émile Gallé, and Hendrik Petrus Berlage. He also influenced the first modern architects, Frank Lloyd Wright, Mies van der Rohe, Auguste Perret, Louis Sullivan, and Le Corbusier, who considered Viollet-le-Duc as the father of modern architecture. English architect William Burges claimed that "We all cribbed on Viollet-le-Duc even though no one could read French".

Kenzō Tange (丹下 健三, Tange Kenzō; 4 September 1913 – 22 March 2005) was a Japanese architect. Born in Sakai and raised in China and southern Japan, Tange was inspired from an early age by the work of Le Corbusier and designed his first buildings under Imperial Japan. He first achieved recognition for his projects to reconstruct the destroyed cities of postwar Japan, particularly Hiroshima, where he designed the Hiroshima Peace Memorial Park. His engagement with the Congres Internationaux d'Architecture Moderne in the 1950s made him one of the first Japanese architects to achieve international recognition.

Renowned for synthesizing traditional Japanese styles with modernism, Tange's work was emblematic of the Japanese postwar boom. However, he built major projects on five continents. He was a forerunner, mentor, and patron of the metabolist movement. He was also known as an ambitious, original urban planner whose ideas inspired the reconstruction of cities including Skopje. Tange would continue designing buildings until his death in 2005.

Oscar Ribeiro de Almeida Niemeyer Soares Filho (15 December 1907 – 5 December 2012), known as Oscar Niemeyer (Brazilian Portuguese: [ˈoskaʁ ni.eˈmajeʁ]), was a Brazilian architect considered to be one of the key figures in the development of modern architecture. Niemeyer was best known for his design of civic buildings for Brasília, a planned city that became Brazil's capital in 1960, as well as his collaboration with other architects on the headquarters of the United Nations in New York. His exploration of the aesthetic possibilities of reinforced concrete was highly influential in the late 20th and early 21st centuries.

Both lauded and criticized for being a "sculptor of monuments", Niemeyer was hailed as a great artist and one of the greatest architects of his generation by his supporters. He said his architecture was strongly influenced by Le Corbusier, but in an interview, assured that this "didn't prevent [his] architecture from going in a different direction". Niemeyer was most famous for his use of abstract forms and curves and wrote in his memoirs: