A scorched earth policy is a military tactic which involves destroying anything that might be useful to the enemy while advancing through or withdrawing from an area. The term refers to the practice of burning crops to deny the enemy food sources, although it is by no means limited to food stocks, and can include shelter, transportation, communications and industrial resources, which are often of equal or greater military value in modern warfare, as modern armies generally carry their own food supplies. The practice may be carried out by an army in enemy territory, or by an army in its own home territory.
Military usages
Roman era
Two of the first uses of scorched earth recorded both happened in the Gallic Wars. The first, ironically, was used against their own: The CelticHelvetii were forced to evacuate their homes in Southern Germany and Switzerland due to unfriendly Germanic tribes. To add incentive to the march, the Helvetii destroyed everything they could not bring. After these Germans were defeated by a combined Roman-Gallic force; the Helvetii were forced to rebuild themselves on the shattered German and Swiss plains they themselves destroyed.
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