Scorched earth
A scorched-earth policy is a military strategy that aims to destroy anything that might be useful to the enemy while it is advancing through or withdrawing from a location. Any assets that could be used by the enemy may be targeted, for example food sources, water supplies, transportation, communications, industrial resources, and even the locale's people themselves.
Second Boer War
flush out guerrillas in a series of systematic drives, organised like a sporting shoot, with success defined in a weekly 'bag' of killed, captured and wounded, and to sweep the country bare of everything that could give sustenance to the guerrillas, including women and children ... It was the clearance of civilians—uprooting a whole nation—that would come to dominate the last phase of the war.
As Boer farms were destroyed by the British under their "Scorched Earth" policy—including the systematic destruction of crops and slaughtering of livestock, the burning down of homesteads and farms, and the poisoning of wells and salting of fields—to prevent the Boers from resupplying from a home base many tens of thousands of women and children were forcibly moved into the concentration camps. This was not the first appearance of internment camps, as the Spanish had used internment in Cuba in the Ten Years' War, but the Boer War concentration camp system was the first time that a whole nation had been systematically targeted, and the first in which some whole regions had been depopulated.