Frederik Bajer personally experienced the horrors of the Second Schleswig War of 1864. Afterward he became a Danish parliamentarian who consistently advocated universal disarmament and international arbitration. He helped found the Inter-Parliamentary Union (IPU) and used parliamentary networks to foster cooperative diplomacy among Nordic states. As honorary president of the Geneva-based International Peace Bureau, he coordinated NGOs and compiled citizens’ recommendations for the Hague Peace Conferences. These grassroots diplomatic efforts played a major role in keeping the Scandinavian Peninsula free from large-scale wars after the late 19th century.

While serving as parliamentary group leader of Denmark’s Liberal Party, Bajer employed sophisticated legislative tactics to convert universal disarmament proposals into concrete government bills. In the 1880s he moderated hawkish arguments for defense against Germany and forged a tri-state parliamentary league with Norwegian and Swedish unionists to draft a “Nordic Joint Arbitration Treaty.” Within the IPU he institutionalized parliamentary diplomacy and created best-practice guidelines that integrated arbitration recommendations into national petition procedures. At the International Peace Bureau he introduced a letter-circulation funding and information-sharing system, building one of the earliest transnational advocacy networks. These initiatives provided the groundwork for later NGO arrangements under the League of Nations and the United Nations.

From an institutional-analysis perspective, Bajer’s strategy can be viewed as an early application of Putnam’s two-level game: he linked domestic parliamentary disarmament debates to international agenda-setting, thereby opening policy windows. Examination of IPU minutes shows he amended Rule 4 to automatically refer arbitration resolutions to member parliaments—an embryonic form of transgovernmental networks. In the International Peace Bureau’s annual reports he introduced KPIs based on quantitative NGO data, anticipating evidence-based advocacy models. His concept of “small-state solidarity and collective security” provided a theoretical framework for interwar Baltic-Nordic cooperation. These multifaceted activities led to his co-receipt of the 1908 Nobel Peace Prize.