When it was noised abroad with the customary exaggeration that the monopoly of Golconda and the Brazils was at an end and that diamonds grew wild on the South African veld, a wide extent of country was explored and the precious crystallized carbon was found in districts separated by many hundreds of miles. In certain places, one of which became known as the town of Kimberley, it was ascertained to recur in a constant proportion of the contents of the "pipes" or volcanic tubes which rose through the surface strata.

The pioneers of Kimberley took possession of the diamondiferous grounds without ascertaining to whom they belonged, and when their value became positive the question of ownership arose. The boundaries of the districts administered by the Cape Colony, the Orange Free State, and the Transvaal respectively were, as regards territory, supposed to be of little account, vague, ill-defined, and unsurveyed; and the districts themselves were occupied by native tribes of nomad habits. About the middle of the XIXth century a Hottentot chief named Waterboer came up out of the West and squatted in the districts lying between the Orange and the Vaal. His rights, such as they were, were assumed or acquired by the Cape Government, which soon became involved in controversy with the Orange Free State as to their extent and nature. Finally the British Empire secured a good title to the estate by the payment of £90,000. But the Orange Free State not unnaturally, when the value of the Diamond Fields increased day by day, soon began to think that it had parted with a profitable possession for an inadequate return. The feeling rankled; and the confident expectation of recovering Kimberley sold for a song tempted Bloemfontein into the fatal alliance with Pretoria.

In 1871 a sickly youth named Cecil Rhodes came from England to South Africa in search of health, which after a short sojourn in Natal he found at Kimberley. The prospects of the place favourably impressed him, and he soon laid in it the foundations of his fortune; but six years later the future of Kimberley was still precarious and the discovery of gold in a remote district of the Transvaal sucked thither the greater proportion of the citizens, who, however, found that they had not bettered themselves by the change and returned to the pipes: and soon nearly a hundred companies, syndicates, and private adventurers were groping for diamonds over an area of less than two hundred acres. The waste of energy was manifest to Rhodes, who in 1888 completed, with the help of the Rothschilds, the task upon which he had been engaged for some years, the amalgamation of the conflicting and overlapping diamond interests under the name of the De Beers Consolidated Mines. It was soon found that the new industry was insufficiently protected by the existing criminal law and a new felony was created by the Illicit Diamond Buying Act.

It has been for several centuries the practice of Great Britain to entrust to private companies the imperial responsibilities which she is reluctant to assume and to let out to contractors, who can be repudiated if they fail and expropriated if they succeed, the job of expanding an Empire. Of this policy the most prominent instance is the East India Company, a commercial venture which obtained from Queen Elizabeth a charter empowering it to trade with the East and which, though connected with Great Britain only by the slender thread of an ocean track of 12,000 miles, maintained itself for two centuries and a half with ever increasing territory and authority until it became a great military Empire. Other examples of lower degree are the Hudson's Bay Company and the Borneo Company. The De Beers Company provided out of its abundance large sums for exploration and settlement in South Africa and for the furtherance of the Imperial idea, and it is said that Rhodes spent the whole of one night in arguing with some of the materialistic magnates of Kimberley, before he could induce them to consent to the employment of the resources of the Company in the advancement of his schemes of Empire. He found, however, that these could not be satisfactorily promoted by a Company whose primary interests were commercial rather than imperial; and in 1888 he obtained a charter for the British South Africa Company, an offshoot of the De Beers Company, formed for the purpose of extending the British Empire towards the Equator.

The question of the defences of Kimberley engaged the attention of the De Beers Company some years before the outbreak of the war. Its vulnerability to attack from the Orange Free State, the border of which ran close to the town, was obvious; and in 1896 a depot of arms and ammunition was formed. A military plan of the place was sent to the Imperial authorities and a defence force was also organized. This, however, had in 1899 ceased to exist owing chiefly to the action of Mr. Schreiner, at that time the Premier of the Cape Colony, who in June refused, with complacent optimism, to furnish it with arms, saying that, "there is no reason for apprehending that Kimberley is in danger of attack," and that "the fears of the citizens are groundless and their anticipations without foundation." A battery of artillery was, however, surreptitiously brought up from King Williamstown.

The policy of Schreiner during the months preceding the war is obscure. While refusing help to Kimberley he was allowing munitions of war, which were way billed as pianos and hardware, to pass through the Cape Colony to the Transvaal and the Orange Free State. He does not appear to have been actively disloyal to the Imperial Government and in his own way he probably did his best to keep the peace. His mind was cast in a mould which is not uncommon in the British Empire but which is rarely found outside it. He was more anxious to stand well with its enemies, and like the Unjust Steward to have a claim to a place in their houses, if they were successful, than to work for its security. It was with great difficulty that Sir A. Milner as late as September 18 obtained his consent to the dispatch of a few regulars to Kimberley to form the backbone of a defensive force. He seems to have retained almost to the end, in spite of all indications to the contrary, the belief that the war would be averted or at least that the Orange Free State would not join in it. Yet in this he erred in good company. Mr. Balfour said that if on September 28 he had been asked whether war with the Orange Free State was a probable contingency he would have replied that war with Switzerland was one equally probable; and Lord Lansdowne declined before September 23 to discuss with Lord Roberts the question of operations in the Free State. Buller, with surer insight, had foreseen the alliance as far back as 1881.

The War Office, however, was to a certain extent on the alert and distrusted the optimism of Schreiner and of a high military official who had been for some years in South Africa. Officers were sent to Kimberley to organize a scheme of defence, but having regard to the susceptibility of the Capetown Government it was done secretly and confidentially and Schreiner was outwitted. By October 7 the town, which was under the command of Colonel Kekewich, was secure against a coup de main though not against a vigorous and sustained siege. Little more than an eighth of the garrison was composed of regular troops; the artillery was out of date; rifles and ammunition were deficient. On October 13 Rhodes threw himself into Kimberley and became for better or worse a power in the town. As soon as the siege began the relative value of the chief products of the mines was inverted: water, the most generous gift of nature and hitherto an embarrassment in the workings, became for the time being more valuable than the diamonds.

On October 12 the curtain of the great drama was raised and the first scene presented. It showed the capture of an armoured train on the railway between Kimberley and Mafeking. Kimberley under any circumstances was a prize worth winning. But Kimberley taken with Rhodes as a prisoner of war, the man who had curbed and checked on every side the expansion of the Republics, who had taken Matabeleland on the north and Bechuanaland on the west into the fold of the British Empire, would be more than a prize, would be a triumph. Rhodes metaphorically in chains, and actually paraded as a captive in the streets of Bloemfontein and Pretoria was an alluring prospect.

Great, however, as were the advantages to be gained by the early capture of Kimberley, the object was not pursued with energy and determination. When the siege began on November 6 the situation was in favour of the attack. The Boers were in possession of the railway from Orange River Station to Mafeking: Kimberley was ill-supplied with the munitions and weapons of war and was defended by a force mainly composed of irregulars; it was encumbered with a large native population; and the civil and military authorities were not working in harmony.

The defence throughout was more active than the attack. Reconnaissances and raids against the enemy's positions were made with effect; and the bombardment which followed a rejected summons to surrender did little harm. Communication with the outer world was not seriously impeded. Cattle grazed almost with impunity inside the line of investment and several thousands of the natives escaped.