This final paper deals with interventions made by Historicist architect Friedrich Schmidt on the Neo-Romanesque Đakovo Cathedral, whose construction was initiated by Bishop Josip Juraj Strossmayer in 1866. Despite being predominant, the Romanesque architectural style is not the only prevalent architectural style here as the cathedral features and unites Neo-Gothic and Neo-Byzantine elements. After Karl Rösner's death, Schmidt became the chief architect in 1870. He continued working on it until 1882 when the cathedral was consecrated. During this period Schmidt finished the work of his predecessor and initiated a lot of projects with the help of a lot of associates and colleagues, particularly architect Herman Bolle, thus justifying the choice made by Strossmayer. Since Rösner did almost the entire exterior of the cathedral in the 4-year period during which he worked on it, Schmidt takes credit mainly ( although not exclusively) for its interior carrying out projects aimed at its architectural decorations, interior furnishings and equipment, which have been completely preserved up to this day, with the exception of the fire-damaged pipe organ and chandeliers.