The National Convention (Dutch: Nationale Conventie, Afrikaans: Nasionale Konvensie), also known as the Convention on the Closer Union of South Africa or the Closer Union Convention, was a constitutional convention held between 1908 and 1909 in Durban (12 October to 5 November 1908), Cape Town (23 November to 18 December 1908, 11 January to 3 February 1909) and Bloemfontein (3 May to 11 May 1909). The convention led to the adoption of the South Africa Act by the British Parliament and thus to the creation of the Union of South Africa. The four colonies of the area that would become South Africa - the Cape Colony, Natal Colony, the Orange River Colony and the Transvaal Colony - were represented at the convention, along with a delegation from Rhodesia. There were 33 delegates in total, with the Cape being represented by 12, the Transvaal eight, the Orange River five, Natal five, and Rhodesia three. The convention was held behind closed doors, in the fear that a public affair would lead delegates to refuse compromising on contentious areas of disagreement. All the delegates were white men, a third of them were farmers, ten were lawyers, and some were academics. Two-thirds had fought on either side of the Second Boer War.
By the end of the convention, the delegates had drawn up a constitution that would, subject to some amendments by the British government, become the South Africa Act, which was South Africa's constitution between 1910 and 1961, when the country became a republic under the Constitution of 1961.
Background
The first attempt to establish a union of the colonies of Southern Africa was in 1858, when burghers of the Orange Free State sent a petition to Sir George Grey, the then Governor of the Cape Colony, requesting the formation of a "compact union" including the Free State, the Cape, and Natal (but excluding the Transvaal). The Volksraad of the Orange Free State followed up the petition with a resolution requesting the State President, Jacobus Nicolaas Boshoff, to communicate with Grey and proposing a conference. When Grey communicated this to the Colonial Secretary, Edward Bulwer-Lytton in London, Lytton replied that the British government was not prepared to resume sovereignty over the Free State, which it had previously controlled as the Orange River Sovereignty between 1848 and 1854.
In 1871, the Cape House of Assembly passed a resolution approving of the idea of union, and in 1872 the House of Commons similarly resolved that it would be "desirable" for a confederation between the colonies and republics of South Africa to be established. In 1874, Lord Henry Carnarvon, who had introduced the British North America Act, sent James Anthony Froude to report on the situation in the region. Froude's presence was, however, resented, due to the South Africans' desire "that union should come from within, not dictated by Downing Street". Froude's report led to the British Parliament passing the South Africa Act, 1877, "for the Union under one Government of such of the South African Colonies and States as may agree thereto". It would have modeled the South African union on the Canadian model, but "South Africa had hardly been consulted" in its promulgation and no Cape parliamentarians were willing to sponsor it locally. The Act expired in August 1882, without being implemented.
The First Boer War (1880 to 1881) intervened in the journey toward union, and it was not until 1889 when a customs union was formed between the Cape and the Free State, which were joined in 1899 by the other territories with the exception of the Transvaal. The Second Boer War (1899 to 1902), which the British won, led to the formerly-independent Boer republics becoming British colonies. The customs union was renewed in 1903, now including the Transvaal.
In 1907, the High Commissioner for Southern Africa, Lord William Selborne was tasked with preparing a report on the disunion of the colonies, titled Review of the Present Mutual Relations of the British South African Colonies, described as an equivalent of the Durham Report. The report regarded the disunion in the region as artificial, and noted the shared "Native problem" and fiscal and economic matters. At this time the white population of the four colonies stood at around one million, with natives numbering five million.