Tweeting Peace: The UN’s Use of Twitter to Legitimate its Peacekeeping Activities

International organisations (IOs) are active participants in the world of social media. But while IOs’ presence and activity on social media have been significantly increasing over the last decade, the scholarly literature is only beginning to take note of the practice and purposes of such engagement. The strategic use of various social media channels by IOs and their extensive communication output about their activities and operations continue to remain poorly understood. In this paper, we ask why and how the UN utilizes Twitter to communicate about its flagship activity, namely, peacekeeping operations. We develop the argument that Twitter primarily serves the UN as a means to legitimate the moral authority of its peacekeeping missions by strategically communicating moral and normative claims. Therefore, the UN utilizes Twitter to communicate the traditional idea of non-coercive peacekeeping rather than about the actual practice itself that is increasingly more robust. The paper utilizes Twitter scraping and quantitative methods derived from computational data science to analyze all of the tweets published by the UN peacekeeping accounts. The study of the large-n dataset demonstrates long-term communicative trends that give insight into the legitimation strategies present within the UN peacekeeping communication. Our paper thus builds and contributes to the scholarship on legitimation of authority of IOs and aids our understanding of IOs’ communicative role and influence in international relations. Furthermore, our paper offers the first systematic and comprehensive analysis of the communication output and influence of UN Peacekeeping communication.