Paul Citroen was a German-born Dutch artist whose career bridged the worlds of Dada, the Bauhaus, and Dutch modernism.Paul Citroen was a German-born Dutch artist whose career bridged the worlds of Dada, the Bauhaus, and Dutch modernism. He is best known for his photomontage Metropolis (1923), a monumental assemblage of over two hundred newspaper and postcard images depicting an imagined future city, which is widely credited as an influence on Fritz Lang's landmark film of the same name. Citroen studied at the Weimar Bauhaus between 1922 and 1924, where he worked under Paul Klee, Wassily Kandinsky and Johannes Itten, and exhibited Metropolis at the school's first public exhibition in 1923. His photomontage practice — rooted in the Dadaist milieu of Berlin, where he had been close to John Heartfield and George Grosz — reached its fullest expression between 1929 and 1935, a period of intense photographic activity in the Netherlands. Beyond photomontage, Citroen was also a painter, portraitist and dedicated educator, founding the New Art School in Amsterdam in 1927 and later teaching at the Royal Academy of Art in The Hague until 1960. His archive, comprising hundreds of thousands of photographs and collages, is held at Leiden University and the Nederlands Fotomuseum in Rotterdam. As both artist and teacher, Citroen played a formative role in shaping a generation of Dutch artists, and his work remains a pivotal reference point for the history of collage, photomontage and the European avant-garde.