[4] In July 1888, he received a doctorate from the University of Leipzig in German philology and literature under Friedrich Zarncke.

In October 1888, Zarncke helped in Fiedler becoming a lecturer in German at Queen Margaret College and the University of Glasgow until 1890.

[3] In July 1907, Fiedler was appointed the first Taylor Professor of the German Language and Literature at the University of Oxford[7] and a Fellow of The Queen's College.

Fiedler edited a number of books related to German studies during his career,[13] particularly an anthology of German verse (Das Oxforder Buch Deutscher Dichtung vom 12ten bis zum 20sten Jahrhundert, with a foreword by Gerhart Hauptmann, Oxford 1911, 2nd edn.

Fiedler never published a full-length scholarly monograph, but focused on pedagogy and collecting manuscripts of German authors.

[14] In 1899, Hermann Fiedler married his former pupil Ethel Mary (1870/71–1933, a daughter of Charles Harding), who wrote a diary covering their marriage between 1899 and 1922.