In this introduction to the special issue on peace history, the emergence of this sub-field of both history and peace research is briefly described, and some of its organizational aspects as well as scholarly achievements are highlighted. The increasing breadth of peace history since its establishment in the 1960s is illustrated, particularly through its focus on grass-roots peacemaking and attention to topics that in the past have been frequently marginalized by mainstream history (with its concentration on traditional diplomatic history and elite foreign policy decisionmaking). The growth of civil society and citizens’ increasing involvement in issues concerning war and peace are providing a rich source for historical analysis. A summary is included of the six case studies which follow. They deal with such subjects as womens anti-war campaigning in the 1930s, conscientious objectors in the 1940s and the anti-nuclear movements of the 1970s and 1980s. Spanning the 20th century and drawn from three continents, these studies show the potential as well as the difficulties inherent in popular peace advocacy.