Following the campaign against Dingane, in 1839 the Voortrekkers, under Pretorius, formed the Boer republic of Natalia, south of the Tugela, and west of the British settlement of Port Natal (now Durban). Mpande and Pretorius maintained peaceful relations. However, in 1842, war broke out between the British and the Boers, resulting in the British annexation of Natalia. Mphande shifted his allegiance to the British, and remained on good terms with them.
In 1843, Mphande ordered a purge of perceived dissidents within his kingdom. This resulted in numerous deaths, and the fleeing of thousands of refugees into neighbouring areas (including the British-controlled Natal). Many of these refugees fled with cattle. Mpande began raiding the surrounding areas, culminating in the