Namibia–South Africa border

A British colony meets a German one

Britain took Cape Town and the land around it from the Dutch in 1814 and ran it as the Cape of Good Hope Colony, which grew north and east through the 19th century.^[1] On the coast further north, a German merchant, Lüderitz, got a land concession from a local chief at Angra Pequena (today's Lüderitz). It was taken to run from the north bank of the Orange to the 26th parallel.^[1]

Germany declared a protectorate over the concession on 16 August 1884. That September it put the coast north to Cape Fria under German protection too, except for Walvis Bay, which Britain had already claimed.^[1] German South-West Africa then spread quickly inland through agreements with local rulers, proclamations and treaties.^[1]

The 1890 line: a riverbank and a meridian

On 1 July 1890 Britain and Germany signed an agreement that split their spheres of influence from the Atlantic inland to where the Linyanti meets the Zambezi. The same agreement also dealt with Zanzibar and Heligoland. In effect it drew the line between the Cape Colony and South-West Africa that is still the border today.^[1]

The line starts at the mouth of the Orange River and follows its north bank upstream to the 20th meridian east. That puts the whole river on the British, now South African, side. From there it runs straight north along the meridian to the Nossob.^[1] A British Order in Council of 3 October 1895 fixed the point where the meridian meets the Nossob, now the tripoint with Botswana. An Anglo–German boundary commission, first appointed in 1898, surveyed and marked the meridian through the desert.^[1]

“To the south by a line commencing at the mouth of the Orange River, and ascending the north bank of that river to the point of its intersection by the 20th degree of east longitude.”^[1]

From mandate to independence

After the First World War, Germany gave up its colonies in the Treaty of Versailles. On 17 December 1920 the League of Nations gave South Africa a mandate to run South-West Africa. A mandate meant governing a territory on the League's behalf rather than owning it.^[1] After the Second World War the UN General Assembly turned down South Africa's request to annex the territory, and South Africa refused to place it under a UN trusteeship.^[1]

On 27 October 1966 the General Assembly ended South Africa's mandate, and in 1968 it renamed the territory Namibia. In a 1971 advisory opinion the International Court of Justice concluded that South Africa's presence there was illegal and that it must withdraw.^[1] Namibia became independent in 1990.^[4] So from 1920 until 1990 South Africa ran the land on both sides of the line. Only since 1990 has it divided two independent countries.^[1][4]

Walvis Bay: the second border that disappeared

In 1972 the US Geographer counted a second, separate stretch of this border: 69 miles around Walvis Bay, a South African enclave on the Namibian coast.^[1] Britain claimed the bay on 12 March 1878, and the Cape Colony annexed the 434-square-mile territory in August 1884.^[1] Britain and Germany could not agree where its southern edge lay, so in 1911 a Spanish arbitrator, Joaquín Fernández Prida, settled it.^[1]

From 1922 South Africa ran Walvis Bay as part of South-West Africa. In 1977, as talks on Namibian independence gained pace, it moved the port back under its Cape Province.^[4] UN Security Council Resolution 432 (1978) declared Walvis Bay an integral part of Namibia.^[5] Namibia's constitution claimed the enclave, but it stayed South African when Namibia became independent in 1990.^[4][6] A Joint Administrative Authority ran it from November 1992, and on 1 March 1994 South Africa transferred Walvis Bay and the offshore Penguin Islands to Namibia.^[5]

Bank or middle?

The 1890 agreement put the border at the high-water level of the Orange's northern bank.^[7] Namibia's 1990 constitution says instead that the country's southern boundary extends to the middle of the river.^[6] According to Climate-Diplomacy, promises were apparently made before independence that the border would move to mid-river. In 2001 South Africa reportedly told Namibia that Africa's colonial borders should stay as they are, under the principle of uti possidetis (keeping the borders inherited at independence).^[7]

The stakes go beyond the river itself. Where the land border reaches the coast decides where the two countries' 200-nautical-mile sea zones meet, which affects mining and marine resources.^[7]

The Namibian dates the dispute to 1991. A joint committee of experts set up in 2016 finished a report in 2017, and ministers discussed it at Swakopmund in October 2024 without a final agreement.^[8][3] At the fourth Namibia–South Africa Binational Commission in Pretoria in July 2026, the two sides again failed to settle it. President Netumbo Nandi-Ndaitwah said she and President Cyril Ramaphosa would take it up directly at a meeting planned for early 2027.^[3]

“…and its southern boundary shall extend to the middle of the Orange River.”^[6]