An architect and art historian Neumann, Wilhelm Johann Carl arrived in Riga in 1863, but in 1864, he started to work in Daugavpils. In 1875 and 1876, he studied at the Imperial Academy of Arts in Saint Petersburg. From 1878 to 1895, he was a city architect of Daugavpils. In 1892, he was promoted and became doctor of philosophy and art (Dr. phil. et bon art) at the University of Leipzig. In 1895, Neumann acquired a right to design buildings from the Technical Committee for Construction of the Ministry of the Interior in Saint Petersburg and moved to Riga. Between 1895 and 1906, he was a scientific and technical supervisor of restoration works in the Riga Dome Cathedral and Monastery complex. From 1899 to 1901, Neumann was an associate professor of art history at Riga Polytechnic Institute, but from 1905 to 1919, he was a director of the Riga City Museum of Art. He was a member, an honorary member or a chairperson in several scientific, historical, literary and genealogical societies. Neumann was the author of numerous residential buildings, factories, churches and other public buildings built in Riga, Daugavpils, Kuldīga and other cities and towns of Latvia, as well as of a few manor houses. Several of his buildings, e.g. the apartment house at Brīvības iela 55 in Riga, are the earliest examples of Art Nouveau. Neumann published more than 60 books and articles on art and architecture.