Karin van Leeuwen is assistant professor in European political history in the History Department and postdoc at the University of Copenhagen's SAXO Institute. Previously she worked as a lecturer in European Studies at the University of Amsterdam and as a researcher at the Huygens Institute of Netherlands History.

Her research focuses on the intersections of political and legal history, whether on a national (constitutional), European or international level. Her work on Dutch constitutional reforms resulted in a PhD (NIjmegen, 2013) titled Uit het spoor van Thorbecke. Grondwetsherziening en staatsvernieuwing in naoorlogs Nederland (Boom 2013) and the source edition Over de grondwet gesproken (2019). She also published various articles on the Dutch reception of and contributions to European (EEC/EU) law. Her current post doc project, which is part of a larger project regarding the history of the League of Nations and international law (1919-1945), focuses on transnational networks of law professors and practitioners in the interwar years.