The majority of Voortrekkers, however, neither settle between the Orange and the Vaal nor trek to the north, but move northeastward around Lesotho and travel down toward the sea into Zulu-ruled areas of southeastern Africa.

The leader of this group, Piet Retief, attempts to negotiate with Dingane for permission to settle in relatively sparsely populated areas south of the Tugela River.

Dingane is at first receptive to Retief's entreaties, but then, apparently fearing that the introduction of European settlers will undermine his authority, he has Retief and seventy of his followers killed while they are at his capital in February 1838.

Dingane now sends out Zulu regiments to eliminate all Voortrekkers in the area; they kill several hundred men, women, and children and capture more than thrity-fibve thousand head of cattle and sheep.

Not all of the settlers are killed, however, and in December the survivors, reinforced by men from the Cape Colony, march five hundred strong to avenge the deaths of Retief and his followers. Commanded by Andries Pretorius, the Voortrekkers pledge that they will commemorate a victory as a sign of divine protection.

They then meet and defeated Dingane's army at the Battle of Blood River.

Their victory will be celebrated each year on December 16, the Day of the Vow.

King Dingane, kaSenzangakhona of the Zulu people, asks that Voortrekker Piet Retief and his party retrieve some cattle stolen from him by a local chief.

This Retief and his men do, returning on February 3, 1838.

The next day, a treaty is signed, wherein Dingane cedes all the land south of the Tugela River to the Mzimvubu River to the Voortrekkers.

Celebrations follow.

On February 6, at the end of the celebrations, Retief's party are invited to a dance, and asked to leave their weapons behind, which they do willingly to show good faith.

At the peak of the dance, Dingane leaps to his feet and yells "Bambani abathakathi!" (isiZulu for "Seize the wizards").

Retief and his men are overpowered, taken to the nearby hill kwaMatiwane, and executed.

Some believe that they were killed for withholding some of the cattle they recovered, but it is likely that the deal was a ploy to overpower the Voortrekkers.

Dingane's army now attacks and massacres a group of five hundred Voortrekkers—men, women and children—camped nearby.

The site of this massacre is today called Weenen, (Afrikaans for "to weep").

The remaining Voortrekkers had elected a new leader, Andries Pretorius, after which Dingane suffers a crushing defeat at the Battle of Blood River on December 16, 1838, when he attacks a group of four hundred and seventy Voortrekker settlers led by Pretorius.

An estimated three thousand Zulus are killed, while three Voortrekkers are slightly wounded.

Dingane's commander at the battle is Ndlela kaSompisi.

Following this defeat, Dingane burns his royal household and flees north.