From Wikipedia

 The War Files - The Boer War

 During the Second Boer War, the UK pursued the policy of rounding up and isolating the Boer civilian population into concentration camps. The wives and children of Boer guerrillas were sent to these camps with poor hygiene and little food, although this was remedied to some extent as time went on. The death and suffering of the civilians, according to many scholars, is what broke the guerrillas' will. The "pacification" theory has been repeated many times in warfare since.