(1879), decisive six-month war in eastern South Africa, resulting in British victory over the Zulus. Before the war the Tugela River formed the boundary between Zululand and the British (British Empire) colony of Natal. Cetshwayo (q.v.) became king of the Zulus in the early 1870s. Unwilling to submit to British hegemony, he assembled a well-disciplined army of 40,000 to 60,000 men. Late in 1878 he received an ultimatum from Natal to disband his army and pay reparations for alleged insults. When he did not respond, British troops invaded under the leadership of Lord Chelmsford. Although the January 1879 rains impeded travel and the tall grasses of Zululand blocked their view, the invaders advanced into Zululand without taking normal precautions (such as scouts and sentries). The Zulu army attacked and annihilated the central British column at Isandhlwana, killing 800 British soldiers and taking nearly 1,000 rifles, with ammunition.

Later, British reinforcements arrived and Cetshwayo fled. The British advantage met a setback in April with the unsolicited arrival of a French prince, Napoleon III's son, in search of adventure. He joined a British expedition, underestimated the enemy, and was killed in a surprise attack in May. His death was an embarrassment for the British, who had been unable to protect him. Their victories continued, nevertheless. In July Cetshwayo was decisively defeated at Ulundi. Zululand then came under informal British control. It was annexed to Natal in 1887.