Ulrich Pfister obtained his PhD from the University of Zürich, Switzerland, in 1984. Since 1996, he is Professor of Social and Economic History at the University of Münster, Germany. His research covers agricultural history, proto-industrialization, demographic history, and historical national accounts. Nikolaus Wolf obtained his PhD from Humboldt University Berlin in 2003. After positions at the London School of Economics, Free University Berlin, and the University of Warwick, in 2010 he became Professor of Economics and Economic History at Humboldt University. He works on the economic history of Europe in the 19th and 20th centuries, with a focus on economic geography, trade, borders, and identity.