The unexpected appearance of enemy troops on a flank or from behind can damage an army's morale, and if a force is encircled it can be deprived of supplies or attacked from any side. Ultimately, if completely cut off, it must cut its way out, surrender or fight to the death. Envelopment is the classic example of maneuver warfare and has produced some of the most decisive victories in history

While envelopment certainly isn't the most fascinating war tactic ever performed, it has been around for a very long time. Sun Tzu speculated against using the tactic in The Art of War but history has since shown it to be extremely efficient with great generals such as Alexander the Great, Khalid bin Waleed, Hannibal, Yi Sun Shin, Shaka Zulu, Wallenstein, Nader Shah, Napoleon, Moltke, Heinz Guderian, von Rundstedt, von Manstein, Zhukov, and Patton all using it.

The tactic was employed at Stalingrad in Operation Uranus, beginning on November 19, 1942. With the Germans pinned down and unable to maneuver, the Soviets delivered a heavy artillery bombardment from 3,500 guns on Romanian and Italian positions on either side of the city, then unleashed several armored formations, including three tank corps. They combined mobility and speed with devastating firepower, driving deep behind German lines to cut off and then defeat the entire German army in Stalingrad.

There are 4 types of envelopment: Single envelopment (flanking maneuver), Double envelopment (pincer movement), encirclement, and vertical envelopment.