Every battle has its own language. Here are the key terms of military history, from the ancient phalanx to the blitzkrieg of the twentieth century, each explained in plain words and linked to a battle where it decided the day. Read the term, then go see it in action.
- Phalanx
- A dense rectangular block of infantry fighting shoulder to shoulder with long spears and overlapping shields, so the enemy meets a wall of points. The signature formation of the ancient Greeks. See it hold the pass at Thermopylae and win the day at Gaugamela.
- Hoplite
- A citizen-soldier of the ancient Greek city-states, armored with a large round shield, spear and helmet, who fought in the phalanx. The hoplites of Athens turned back Persia at Marathon.
- Legion
- The main infantry unit of the Roman army, a few thousand men in flexible smaller units that could maneuver where a rigid phalanx could not. Rome's legions finally beat Hannibal at Zama.
- Double envelopment
- A maneuver that attacks both enemy flanks at once and closes behind them, surrounding the force. Hannibal's execution of it at Cannae in 216 BC is the classic example, still taught in academies today.
- Flanking
- Attacking the side or rear of an enemy line, where it is weakest, instead of hitting the strong front head on. Alexander opened a gap and struck the flank at Gaugamela; Napoleon turned the allied flank at Austerlitz.
- Longbow
- A tall wooden war bow that could send massed volleys of arrows over long range. English longbowmen broke French cavalry and chivalry at Crecy and again at Agincourt.
- Siege
- An operation to capture a fortified place by surrounding and cutting it off, then starving, storming or breaching it, rather than fighting in the open. The siege of Vienna in 1683 and the siege of Tenochtitlan in 1521 both decided empires.
- Cavalry charge
- A massed attack by mounted soldiers at speed, using shock and momentum to break a line. The winged hussars delivered one of the largest in history at Vienna; the doomed Charge of the Light Brigade rode into disaster at Balaclava.
- Line of battle
- A naval formation in which warships sail in a single line so each can fire its broadside, the origin of the term ship of the line. Nelson deliberately broke the enemy line at Trafalgar.
- Trench warfare
- Static fighting from lines of fortified ditches, where attackers must cross open ground into machine guns and artillery. It defined the Western Front at the Somme and Verdun.
- Attrition
- Winning not by one decisive blow but by steadily wearing the enemy down until they cannot replace their losses. Verdun in 1916 was the pure, terrible expression of it.
- Blitzkrieg
- Lightning war: a fast offensive combining tanks, aircraft and infantry to punch through and encircle before the enemy can react. Germany used it to great effect early in the Second World War, until it stalled outside Moscow.
Want to see these in full? Start with the greatest battles of all time, or meet the leaders who used them in the greatest military commanders in history.
How to use this glossary
Military history has a language of its own, from the phalanx of the ancient world to the blitzkrieg of the twentieth century. This glossary gathers the key terms you will meet across our battle guides and explains each in plain English, so the tactics and formations behind the great battles make sense.
Once a term clicks into place, see it in action in the greatest battles of all time or the greatest military commanders in history.