The border between modern-day Botswana and Namibia was established along the “main channels” of the rivers along the mutual frontier by an 1890 treaty between the UK and Germany, the respective colonial powers at the time.1 The ambiguity of this delineation has led the governments of both countries to issue competing claims on territory in the border rivers, with the Sedudu Islands representing a particularly contested prize. While the Islands themselves have some value as tourist destinations, the primary concern was the division of water reserves that legal jurisdiction over the territory would offer.2 Tensions between the administrations of each state were heightened when the Namibian government proposed building a 250km water pipeline from the Okavango River to feed its growing needs.3 Such a development would have potentially threatened the Okavango Delta in Botswana with desertification. In 1991, Botswana deployed troops to the region, and in 1993, soldiers from both countries exchanged fire in the area. In the ensuing years, both countries built up their military forces along the border. Tensions continued to rise in 1996, when Botswana acquired tanks and fighter-bombers and Namibia bought a large shipment of arms from Russia.4 Given the high numbers of military personnel in the region and the history of clashes along the border, the dispute ran the risk of sparking an interstate conflict and represented a pervasive threat to peace and stability in the region.
The Government of Zimbabwe provided good offices to facilitate negotiations in 1996 which, although ultimately fruitless, inspired the Botswanan and Namibian governments of both states to submit the dispute to the International Court of Justice.5 Judges at the Court considered the case until December 1999, when they ruled that the territory was lawfully that of Botswana, but both states should enjoy freedom of navigation on the river.6 Although this decision resolved the conflict, Botswanan and Namibian troops almost clashed in 2015.7 Recognising the continued risk posed by the frontier, the governments of both states invited the African Union to mediate the negotiation of a formal boundary treaty in 2016 to not only reduce the likelihood of such clashes, but to also facilitate movement and trade. The African Union Border Programme advised the process. On 6 February 2018, representatives from both states signed the Boundary Treaty in the Namibian capital, Windhoek.8