Editing Scorched earth (section)

===Napoleonic Wars===
During the third [[Peninsular War|Napoleonic invasion of Portugal]] in 1810, the [[Portuguese people|Portuguese]] population retreated towards [[Lisbon]] and was ordered to destroy all the food supplies the French might capture as well as forage and shelter in a wide belt across the country. (Although effective food-preserving techniques had recently been invented, they were still not fit for military use because a suitably-rugged container had not yet been invented.){{sfn|Pivka|2013}} The command was obeyed as a result of French plundering and general ill-treatment of civilians in the previous invasions. The civilians would rather destroy anything that had to be left behind, rather than leave it to the French. When the French armies reached the [[Lines of Torres Vedras]] on the way to Lisbon, French soldiers reported that the country "seemed to empty ahead of them". Low morale, hunger, disease and indiscipline greatly weakened the French army and compelled the forces to retreat, see also [[Attrition warfare against Napoleon]].

[[File:Napoleons retreat from moscow.jpg|thumb|upright=1|right|Napoleon's retreat from Moscow]]
In 1812, Emperor [[Alexander I of Russia|Alexander I]] was able to render [[Napoleon's invasion of Russia]] useless by using a scorched-earth policy.{{sfn|Riehn|1990|p=321}} As Russians withdrew from the advancing French army, they burned the countryside over which they passed ([[Fire of Moscow (1812)|and allegedly Moscow]]),{{sfn|Chandler|1966|p=813}} leaving nothing of value for the pursuing French army. Encountering only desolate and useless land Napoleon's [[Grande Armée]] was prevented from using its usual doctrine of living off the lands that it conquered. Pushing relentlessly on despite dwindling numbers, the Grand Army met with disaster as the invasion progressed. Napoleon's army arrived in a virtually-abandoned [[Moscow]], which was a tattered starving shell of its former self, largely because of scorched-earth tactics by the retreating Russians. Having conquered essentially nothing, Napoleon's troops retreated, but the scorched-earth policy came into effect again because even though some large supply dumps had been established on the advance, the route between them had both been scorched and marched over once already. Thus, the French army starved as it marched along the resource-depleted invasion route.{{sfn|Kuhn|2008}}