The proliferation of Small Arms and Light Weapons (SALW) has remained one of the most significant threats to Nigeria’s national security, socio-economic development, and regional stability since the post-independence era. This article examines the historical evolution of SALW proliferation in Nigeria from a diplomatic and national security perspective. Using a historical and qualitative research approach, the study draws on, government publications, international treaties, policy documents, reports of regional and international organizations, and existing scholarly literature. It explores the domestic and transnational drivers of illicit arms trafficking, the role of porous borders and regional conflicts, and the effectiveness of Nigeria’s diplomatic engagements in addressing the challenge through bilateral, regional, continental, and global security frameworks. Particular attention is given to Nigeria’s participation in the ECOWAS Convention on Small Arms and Light Weapons, the African Union’s arms control initiatives, the United Nations Programme of Action on Small Arms and Light Weapons, the Arms Trade Treaty, and intelligence-sharing mechanisms for transnational crime prevention. The article argues that while Nigeria has demonstrated considerable diplomatic commitment to international arms control and regional security cooperation, weak institutional coordination, inadequate border management, corruption, and limited implementation of existing legal frameworks have constrained policy effectiveness. It concludes that sustainable control of illicit arms proliferation requires stronger security diplomacy, enhanced intelligence cooperation, integrated border governance, effective arms-tracing mechanisms, and deeper collaboration with regional and international partners. The study contributes to the growing scholarship on the intersection of diplomacy, arms control, and national security in Africa by demonstrating that diplomatic engagement is indispensable to addressing the transnational dimensions of SALW proliferation.

Keywords: Small Arms and Light Weapons; Arms Control Diplomacy; Nigeria’s Foreign Policy; National Security; Transnational Crime.