In October 1837, Voortrekker leader Piet Retief descended the Drakensberg passes with his people, seeking land free from British control. He chose a site for his future capital and traveled to the royal kraal of Dingane, king of the Zulus, to negotiate a cession. Dingane agreed to grant the land south of the Tugela River on one condition: Retief must first recover cattle stolen by a rival chief. Retief obliged. On 4 February 1838, with the help of missionary Francis Owen, the two leaders signed a deed of cession. Celebrations followed for two days. Then, on 6 February, Dingane invited Retief's party to a farewell dance and asked them to leave their weapons behind. At the height of the dancing, Dingane leapt to his feet and shouted "Bambani abathakathi!" -- "Seize the wizards." Retief and his entire party, sixty-six white men and thirty-four Khoikhoi servants, were dragged to the hill of kwaMatiwane and killed.

Dingane's impis did not stop with Retief. On the same day, Zulu forces crossed the Tugela and attacked Boer encampments scattered across the countryside. In a single week, roughly 600 Voortrekkers -- men, women, and children -- were killed. The site of one of the worst massacres was later named Weenen, the Dutch word for weeping. British settlers at Port Natal sent a relief force of twenty Europeans and 700 allied Zulus under Robert Biggar, but they were overwhelmed on 17 April. Only four Europeans survived. The pursuing Zulu forces attacked Port Natal itself, driving its inhabitants to shelter aboard a ship in the harbor. When the violence subsided, fewer than a dozen Britons remained. Boer counterattacks also met disaster: 400 men under Hendrik Potgieter and Piet Uys marched against Dingane, fell into a trap, and barely escaped. Uys and his fifteen-year-old son Dirk were among the dead.

Reinforcements arrived toward the end of 1838, and in December, 464 Boers set out under Andries Pretorius to confront the Zulu army. They moved carefully, mindful of the disasters that had come before. On 9 December, the men gathered under open sky and took a solemn vow: if God granted them victory, they would build a church and commemorate the day forever. A week later, laagered near the Umslatos River, they were attacked by more than 10,000 Zulu warriors. After three hours of fighting, the Boers had killed thousands while suffering fewer than a dozen wounded among their own. The river itself turned red -- and entered history as Blood River. Pretorius pressed his advantage, allying with Dingane's brother Mpande and seizing 36,000 head of cattle. At the Battle of Maqongqo, Dingane was crushed and fled into exile, where he was assassinated near the Swazi border. Pretorius proclaimed the Natalia Republic.

The Boers founded Pietermaritzburg as their capital, naming it for leaders Piet Retief and Gerrit Maritz. A volksraad of twenty-four members governed the republic, while the presidency rotated every three months. The result, as historian George McCall Theal observed, was "utter anarchy. Decisions of one day were frequently reversed the next, and every one held himself free to disobey any law that he did not approve of." The British, meanwhile, watched from Port Natal with growing concern. They had no desire to establish a colony, but they were determined to prevent the Boers from controlling a coastal harbor. When Pretorius attacked the Xhosa in December 1840, the Cape governor announced his intention to occupy the port. The Boers resisted. In May 1842, Captain T.C. Smith attacked the Boer camp at Congella and was beaten back, losing his guns and fifty men. The Boers besieged his camp.

With the British force trapped and starving at Durban, an old colonial resident named Dick King volunteered to ride for help. On the night of 24 May 1842, he slipped past the Boer outposts and pushed through dense bush toward the military post at Grahamstown -- 360 miles in a direct line, nearly 600 by the route he had to follow. He made it in nine days with a single change of horse, obtained from a missionary in Pondoland. A relief force under Colonel A.J. Cloete arrived by sea on 26 June, and within a fortnight the volksraad at Pietermaritzburg submitted. Lord Stanley consented to Natal becoming a British colony in a despatch dated 13 December 1842, with one fundamental condition: "that there should not be in the eye of the law any distinction or disqualification whatever, founded on mere difference of colour, origin, language or creed." Most of the Boers, unwilling to accept this principle, packed their wagons and trekked back over the Drakensberg into what became the Orange Free State and the Transvaal. By the end of 1843, fewer than 500 Dutch families remained.