Pirenne, Henri (äNrēˈ pērĕnˈ) [key], 1862–1935, Belgian historian. He was for many years a professor of history at the Univ. of Ghent. A leader of Belgian passive resistance in World War I, he was held (1916–18) as a hostage by the Germans. In his History of Belgium (tr., 7 vol., 1899–1932), he showed how traditional and economic forces had drawn Flemings and Walloons together. In Mohammed and Charlemagne (tr. 1939) he attributed the collapse of late Roman–Christian civilization to the spread of Islam; this thesis raised much controversy among historians. Pirenne emphasized the historical role of the capitalist middle class, and in Medieval Cities (tr. 1925) he revolutionized accepted views by attributing the origins of medieval cities to the revival of trade. Other works include Belgian Democracy: Its Early History (tr. 1915) and Economic and Social History of Medieval Europe (tr. 1936).
See studies by A. F. Havighurst, ed. (rev. ed. 1969) and B. P. Lyon (1972).