I know that when Hitler invaded Russia, the Russians used a tactic that they also used on Napoleon where the Russians stayed close to the front lines and when they were being overrun, they would just burn/destroy the city they were fighting in and move further back into Russia. Is there a name for this tactic? Your responses would be greatly appreciated!
It sounds like you're describing the "scorched earth" strategy. Used during a retreat, it's used to inhibit the enemy's advance by preventing them from using captured supplies and by destroying infrastructure.