In the first half of the 19th century a proto-functional style appeared in Slovene architecture. Artistic decisions about public buildings were taken by civil servants educated in Vienna and Prague, rather than by artists or patrons. In 1848 the first architectural competitions were held. The Carniola Construction Society of Ljubljana employed several foreign architects to work in and around the capital, including Pietro Nobile, Friedrich von Schmidt and Emil von Foerster, who introduced Viennese and Graz architecture to the city.

Few cities have had the personal seal of a single architect so strongly impressed upon them as Ljubljana has with Jože Plečnik (1872-1957). Educated in Ljubljana and Graz, he graduated from Vienna as Otto Wagner's student. Among the achievements of his neo-classical style were the renovation of the Hradčani Castle in Prague and the Zacherl House project in Vienna. The continued development of the architectural profession in Slovenia was ensured when the University of Ljubljana was established in 1919, and Jože Plečnik was invited to teach there from 1921. Plečnik believed in the noble mission of the architect and its ethical as well as aesthetic function. He considered traditional heritage not as a restriction, but rather as an inexhaustible source of creativity. Between the two world wars Plečnik was the undisputed authority of Slovene architecture, and his urban plan for Ljubljana (1929) gave him the opportunity to map out and implement his grand vision for the city. Over the course of two decades, with extremely limited financial resources, he married classical architectural forms with his own imaginative ideas to create a series of monumental new buildings (the National and University Library, the Market Collonade, the Mutual Insurance Building, the Flat Iron Building, Žale Cemetary), bridges (Three Bridges, Shoemaker's Bridge) and churches (Church of St Francis of Assisi, Church of St Michael in the Marsh).