Alexander is a professor at the Royal Swedish Academy of Letters, History and Antiquities. His research interests are: anti-Judiac literature in Slavia Orthodoxa, particularly East-Slavia; its textology and dissemination in the 12th-16th centuries; the history of 15th-century Ruthenian Jewry; Russian orthodox culture in Swedish Ingria, 1617-1704; and early modern Swedish-Russian cultural relations.