Double envelopment

Double envelopment is a military tactic, originally seen in land warfare but also at sea, where one force sends units around both sides of its opponent's force. The penetrating forces meet behind the enemy force, isolating it.
It is considered a difficult but decisive maneuver, requiring more coordination than single envelopments (in which one unit penetrates along one side of the enemy, and then turns behind the opposing force to cut it off from its lines of supply and communications). Historical double envelopments often have involved deception, in which a third component of the attacking force is a decoy which feigns a retreat, or offers itself as a tempting target. That deception is combined with the decoy force falling backwards, so that the enemy moves forward in pursuit, unaware of strong forces on both of its flanks.
Classic double envelopments
- Battle of Cannae: Carthage vs. Rome; Carthage, under Hannibal, victorious
- Battle of Marathon: Greeks vs. Persians; Greek victory
American Civil War
- Battle of Chancellorville: Union vs. Confederacy; Union attempt failed
World War I
- Battle of Tannenberg: Germans vs. Russia; German victory
- Schlieffen plan: German invasion of the West; stalemate
World War II
- Operation Uranus: Soviet Union vs. Germany at Stalingrad; Soviet victory
- Capture of Metz: United States vs. Germany at Metz, France; U.S., under George S. Patton, victorious