This article offers a new reading of Germany’s complex political culture, exploring the contributions of pacifists, international feminists, and Social Democrats as proactive, yet marginalized, participants in Weimar-era politics. Through a series of historical events including the No-More-War protests, international education courses, pacifist reading sessions, and a transnational peace exhibit, the author demonstrates dynamic exchanges between party and informal politics on the political Left. This interaction, as well as expanding transnational networks and awareness, opened new political spaces for peace activism in the Weimar Republic, the effects of which still endure today.