During the fourth century, the Goths were converted to Christianity, largely through the efforts of Bishop Wulfila, who invented the Gothic alphabet and translated the Bible into the Gothic language in Nicopolis ad Istrum in today's northern Bulgaria.
As an archaeologist, Dobruský personally headed the excavations of the Zlatna Panega asclepieion in 1903–1906, the Ognyanovo nymphaeum in 1904 and the ancient cities of Oescus (1904–1905) and Nicopolis ad Istrum (1906–1909).