Oscar Schlegelmilch was born in the German town of Suhl as a son of a known porcelain manufacturer, Leonhard Schlegelmilch. When he was 29 he bought a few properties in the town of Langewiesen located in Thuringia, Germany. He built there the porcelain factory. The firm was registered in 1891. Already in 1892, 200 employees started production. In 1905 Theodor Conrad Hinrichs became an equal partner in the factory. In 1914 the enlarged factory exported its products to North America, South America, Nordic countries and Balkans. Employment rose to 300 workers. The Great Depression seriously limited export as well as domestic sale. In 1936 Oscar Schlegelmilch retired from the business. Hans Schlegelmilch, Oscar's nephew, became the sole owner of the factory. Oscar Schlegelmilch died in 1938 in Cologne. The factory was inherited by his widow. In 1952 the business administration was overtaken by the state (GDR). In 1959 a limited partner in the company became the state owned VEB Porzellanwerk "Graf von Henneberg" Ilmenau. The new partner decided in 1971 to close the Langewiesen factory.