FROM POLITICAL OFFENCE TO TERRORIST ACT: THE LEAGUE OF NATIONS’ LEGAL RESPONSE TO INTERNATIONAL TERRORISM AND ITS LEGACY

Abstract

This article examines the League of Nations’ legal response to international terrorism during 
the interwar period, addressing its causes within the longer transformation of politically 
motivated violence from the late nineteenth century to the 1930s. Employing a legal-historical 
methodology, with particular attention to interwar Yugoslav doctrine and legislation, this 
article analyses international conventions, diplomatic practices, and legal doctrines. It argues 
that the League’s counter-terrorism efforts emerged from unresolved tensions between the 
traditional protection of political offenders, the sovereign right to grant asylum, and the 
growing perception that cross-border political violence (especially in cases of state-sponsored 
terrorism) posed a direct threat to international peace. The Marseille assassination in 1934 
was the decisive moment that moved terrorism from a bilateral diplomatic dispute into the 
League’s institutional framework. This paper analyses the drafting of the 1937 Convention for 
the Prevention and Punishment of Terrorism, focusing on the definition of terrorist acts, the 
principle of non-intervention, the protection of public officials and public property, and the 
principle of aut dedere aut judicare. Although these solutions never entered into force, they 
anticipated many central dilemmas in modern international counter-terrorism law. The article 
traces their reception into contemporary international counter-terrorism law, arguing that the 
League's most durable legacy lies not in its best-known initiatives but in the procedural model 
of aut dedere aut judicare.