Leading expert on history of the 20th century and the history of international relations. Warden, St Antony's College. Publications include: Peacemakers: The Paris Peace Conference of 1919 and Its Attempt to End War (2001); The Uses and Abuses of History (2008); The war that ended Peace: The road to 1914 (2013). Has also published on roles and perceptions of gender in history. Recipient of honours and awards for work as a historian, including: Officer of the Order of Canada (2006).