In spite of domestic and international political changes, French and German foreign policies have displayed high degrees of continuity between the late 1950s and the mid-1990s. Over the same time period, the directions of the two states’ foreign policies have also continued to differ from each other. Why do states similar in many respects often part ways in what they want and do? This article argues that the French and German national role conceptions (NRCs) account for both of these continuities. NRCs are domestically shared understandings regarding the proper role and purpose of one’s own state as a social collectivity in the international arena. As internal reference systems, they affect national interests and foreign policies. This article reestablishes the NRC concept, empirically codes it for France and Germany for the time period under consideration, and demonstrates comparatively how different NRCs lead to varying interests and policies across the major policy areas in security, defense, and armament.