Fiedler was born in Prostějov, near Olomouc in Moravia. Fiedler was a pupil of Hugo Erfurth. He was regarded as an eccentric during his apprenticeship in Pilsen, and worked in 1905 and again in 1912 with Rudof Dührkoop in Hamburg, and from 1908 to 1911 with Hugo Erfurth in Dresden. At the 1911 world exhibition in Turin he won first prize and had another exhibition in Prague in 1913. He belonged to the circle of Jaroslav Hašek and Egon Erwin Kisch and in 1916 married Erna Hauswald in Dresden where he occupied a studio at Sedanstraße 7.