This article examines the enduring legal complexities of colonial boundary-making in international law: the Malawi-Tanzania border dispute over Lake Malawi (Nyasa). Malawi's claim to the entire lake is firmly grounded in the 1890 Heligoland Treaty, a formal legal instrument explicitly placing the entire lake within the British sphere. Malawi invokes the principle of uti possidetis juris which mandates inherited colonial geo-bodies. The African Union affirmed uti possidetis juris as a cornerstone of post-colonial African boundary law. Tanzania contests this, advocating for a median line boundary based on principles of customary international law for shared water bodies. Tanzania also cites inconsistent British mandate-era maps. However, International Court of Justice (ICJ) jurisprudence generally subordinates maps to primary textual instruments such as treaties. Although the dispute remained dormant for decades, Malawi's 2011 unilateral awarding of hydrocarbon exploration licenses in the contested lake aggravated the dispute. Although the lake dispute demonstrates that modern African sovereignty draws on uti possidetis juris, this article's conclusion recommends ways African states might move beyond inherited colonial legal frameworks and adopt pragmatic approaches to conflict resolution.
Raege Omar (Thu,) studied this question.