The master's thesis presents an art-history analysis of the parliament building of Duchy Carniola, which was built in Ljubljana at the turn of the 19th century. In the short introductory text, the author placed the mentioned subject in historical context. The first chapter outlines the development of the study of the 19th century architecture (especially the architecture of historicism) in Slovenian art-history. In addition there is a review of past research on the parliament building of Carniola. In the second chapter, the author examined the immediate surroundings in which the discussed building was created with an emphasis on the illustration of urban changes in this area between the end of the 17th and the middle of the 20th century. The third chapter includes an overview of key public commissions in Ljubljana in the late 19th and early 20th century, with a special focus on the style of these public commissions. The fourth chapter presents various historical written sources which testify to the commissioning process for the construction of the Carniolian parliament building. The fifth chapter presents the plans for the building, which were contributed by four different architects. In the sixth chapter, the author examines the work of the builders that collaborated in the construction of the new provincial building. Finally, the last chapter, presents the particulars from the past renovations of the given building, which highlights the degree of conservation of its original design.