Walter Adolph Georg Gropius (18 May 1883 – 5 July 1969) was a German-American architect and founder of the Bauhaus School, who, along with Alvar Aalto, Ludwig Mies van der Rohe, Le Corbusier and Frank Lloyd Wright, is widely regarded as one of the pioneering masters of modernist architecture. He is a founder of Bauhaus in Weimar (1919). Gropius was also a leading architect of the International Style.
Born in Berlin, Walter Gropius was the third child of Walter Adolph Gropius and Manon Auguste Pauline Scharnweber (1855–1933), daughter of the Prussian politician Georg Scharnweber (1816–1894). Walter's great-uncle Martin Gropius (1824–1880) was the architect of the Kunstgewerbemuseum in Berlin and a follower of Karl Friedrich Schinkel, with whom Walter's great-grandfather Carl Gropius, who fought under Field Marshal Gebhard Leberecht von Blücher at the Battle of Waterloo, had shared a flat as a bachelor.
In 1915, Gropius married Alma Mahler (1879–1964), widow of Gustav Mahler. Walter and Alma's daughter, named Manon after Walter's mother, was born in 1916. When Manon died of polio at age 18, in 1935, composer Alban Berg wrote his Violin Concerto in memory of her (it is inscribed "to the memory of an angel"). Gropius and Mahler divorced in 1920. (She had by that time established a relationship with Franz Werfel, whom she later married.)
Gropius married Ilse Frank, known as Ise, on 16 October 1923; they remained together until his death in 1969. The couple adopted Beate Frank known as Ati, the orphaned daughter of Ise's sister Hertha. Ise Gropius died on 9 June 1983 in Lexington, Massachusetts.
Walter's sister Manon Burchard (1880–1975) is the great-grandmother of the German film and theater actresses Marie Burchard and Bettina Burchard, and of the curator and art historian Wolf Burchard.
In 1908, after studying architecture in Munich and Berlin for four semesters, Gropius joined the office of the renowned architect and industrial designer Peter Behrens, one of the first members of the utilitarian school.