Tracing the Application of Modern Principles of International Humanitarian Law in the pre-Christian War between King Duṭugamunu and Elāra in Sri Lanka

The war between King Duṭugamunu and Elāra is the most significant singular war that took place in the pre-Christian period in Sri Lanka. It has the elements of modern international armed conflict (IAC). A local monarch waged it to unify the nation against an invading foreign force led by a foreign ruler who seized power through regicide. This historical conflict sparked extensive debates, criticisms, and varying interpretations, contributing to distortions of factual accounts. The studies analysing this battle from the perspectives of the modern International Humanitarian Law (IHL) is minimal. The branch of public international law that deals with IAC is International Humanitarian Law (IHL). The research problem that was investigated is 'Did the Sri Lankan monarch comply with the modern principles of international humanitarian law when there were no such laws at that time in the world and thereby, does that monarch deserve to be called as the founder of IHL? Accordingly, this study aims at analysing the motives, intentions, and conduct including the pre-conflict, in-conflict, and post-conflict behaviour of key actors and the war's outcome from the perspectives of IHL. The methodology used for this study is literature review. It is qualitative and interpretative in nature. The historical sources, international conventions and national legislations were used as primary and secondary sources for this purpose. The focus of the analysis is the evaluation of IHL principles in the context of the historical war. This study provides a unique analysis that suggests the application of principles akin to modern IHL by the ruling monarch nearly two millennia before the formal establishment of such principles. The major finding is that some 2019 years prior to the international community introduced the modern IHL principles such as humanity, avoidance of unnecessary suffering, proportionality of damages, humane treatment of prisoners of war (POW) etc., the ruling Sri Lankan monarch has recognised and applied them in this war and has recognised the new principle of Eternal Honour to POWs which is yet to recognise by IHL. Keywords: Humanitarian; International; Law; Vijiṭapura; War