A visible sign of changing relations between the Global South and Global North are reparation claims for colonial injustice. An interesting case is the 1904–1907 Namibian Genocide. Germany has recently concluded a draft agreement with Namibia on reconciliation and compensation. Nevertheless, Germany maintains that it is not under any legal obligation to pay reparations. This article challenges that position, arguing that colonial international law was far too ambiguous to support this conclusion. For this purpose, the article contrasts this ‘conventional view’ of colonial international law with post-colonial and pluralistic approaches. Post-colonial approaches reveal colonial-era law as a deeply ambiguous, contradictory practice that mirrors the identity crisis of the colonizers. Pluralistic approaches juxtapose colonial international law with autochtonous views of inter-polity law, i.e., the normative framework governing colonial encounters. To reconstruct autochtonous views, the article draws on letters by Hendrik Witbooi and Maharero, traditional leaders from Namibia, and examines the contours of their inter-polity law relating to territorial sovereignty and warfare. These contending perspectives undermine the cogency with which the conventional view rejects reparation claims. While ambiguity as such does not give rise to compensation claims, other options come to mind, such as a duty to negotiate, shifts in the burden of proof – or a profound recalibration of international law towards greater solidarity.