In 1936, he became Professor of Roman History at the University of Turin, but as a Jew, soon lost his position due to the anti-Jewish Racial Laws enacted by the Fascist regime in 1938, and moved to England, where he remained.
Momigliano visited regularly at the University of Chicago where he was named Alexander White Professor in the Humanities, and at the Scuola Normale Superiore di Pisa.
In his retirement, he was made a distinguished visiting professor for life at the University of Chicago and held fellowships at All Souls College, Oxford and Peterhouse, Cambridge.
[7][8] Momigliano considered it wasteful and "comical" to spend much efforts at identifying and explaining the forces held responsible for the gradual disintegration of the Roman Empire.
[9] In the 1980s, Momigliano and fellow historian Carlo Ginzburg leveled heavy criticism against French philologist Georges Dumézil, whom they charged with being a fascist opposed to "Judeo-Christian" society.