Complex sentence: He previously served as the Deputy-Secretary General of the Académie Diplomatique Internationale in Paris, and Director and Vice President of the Salzburg Global Seminar, as well as a lecturer in the Concentration of History and Literature at Harvard University.
Split into simpler sentences: He previously served as the Deputy-Secretary General of the Académie Diplomatique Internationale in Paris, and Director and Vice President of the Salzburg Global Seminar. Prior to this, he was a lecturer in the Concentration of History and Literature at Harvard University.