He was a major figure in the field of Greek codicology and palaeography and a pioneer of modern scholarship on Byzantine military texts.
Dain’s academic studies were initially delayed by his service in the French Air Force during the First World War, which earned him the Croix de Guerre.
He attended the École du Louvre (1922-1924), where he was a student of Paul Mazon and Edmond Pottier, and was certified in Letters in 1926.
[1] During the Second World War, his active participation in the Resistance earned him the French Médaille de la Résistance.
His publications were especially concerned with the textual histories and manuscript transmission of Greek military writers and of Byzantine legal texts.