[4][1] Olomouc's University professor and dean Jan Hejčl desired to be succeeded one day by Dvornik, but his negative experience as an assistant pastor in Germany (1917-1919), and rising political and anti-Catholic Away from Rome!

Then he returned to home country, became an ecclesiastical history professor at Charles University in Prague, and helped founding the Institute of Slavic Studies and the academic journal Byzantinoslavica.

[3] Despite assured academic career in England, he accepted the invitation to join the Institute of Byzantine Studies at the Dumbarton Oaks Center of Harvard University in the United States.

[7] He was also named Knight of the French Legion of Honour, and in memoriam received Order of Tomáš Garrigue Masaryk (class III).

[1] Dvornik has been credited to have "changed our views of the history of Byzantium, of the Slavs and of the Church of Rome; provided large syntheses of Slavic civilization from its beginnings to the early modern period; and traced the development of Byzantine political ideas from their beginnings in the ancient Orient to their reflections in post-Byzantine Eastern Europe".

[1] Dumbarton Oaks has called him "one of the leading twentieth-century experts on Slavic and Byzantine history and on relations between the churches of Rome and Constantinople".

[2] Jan N. Bremmer considered that the modern use of word "iconoclasm" and study of Byzantine history from an iconoclastic viewpoint in Anglosphere began and was influenced by work of Dvornik and Ernst Kitzinger.

[2][3] Dvornik was hailed for his "erudition",[3] "intelligence, ability to view history in large interconnected units, and sheer passion for writing".

Romilly Jenkins in 1949), specifically on the chapters about South Slavs, Dvornik's contribution was described as "gems of synthesis and compression ... particularly detailed and useful commentary ... constitute in effect a treatise on early Slavic history".