The greatest ambush in history is usually said to be Lake Trasimene in 217 BC, where Hannibal hid his army in the hills above a lakeshore road and destroyed a Roman army in a single morning, with the Teutoburg Forest in AD 9 its closest rival. Other famous ambushes and traps include Roncesvalles in 778, Ain Jalut in 1260, Cajamarca in 1532 and Okehazama in 1560; Pearl Harbor and the Tet Offensive were surprise attacks rather than true ambushes.
An ambush, strictly speaking, is an attack from concealment on an enemy who is on the move. A surprise attack is broader: striking an enemy where or when it does not expect, even in its own base. A lure, such as a feigned retreat, draws the enemy onto ground the attacker has chosen. All three appear below, and we say which is which, because the label tells you whether the victory was won by hiding, by timing or by bait.
Ambushes reward patience and local knowledge more than numbers, which is why so many on this list were won by the smaller side. They also punish one recurring mistake: an army marching without proper scouting, confident that the enemy is somewhere else.
1. Lake Trasimene, 217 BC: the perfect ambush
In the spring of 217 BC Hannibal slipped past the Roman consul Gaius Flaminius and ravaged the country around him, daring him to follow. Flaminius did, hurrying along the northern shore of Lake Trasimene, where the road ran through a narrow strip between the water and a ring of hills. Hannibal had posted his army on those slopes overnight. At dawn, with morning fog rising off the lake1 and hiding the hills, the Roman column marched into the defile, and the Carthaginians came down on it from front, flank and rear at once. Within a few hours the army was destroyed: about 15,000 Romans were killed1, Flaminius among them, and thousands more were taken prisoner.
2. Teutoburg Forest, AD 9: the ambush that lasted days
The Teutoburg disaster was a blunder by the Roman governor Varus, but on the German side it was a masterpiece. Arminius, who knew Roman methods from serving with their army, led three legions with their auxiliaries and baggage2 onto forest tracks squeezed between hills and marshes, then attacked them piece by piece over several days in heavy rain. At Kalkriese, near Osnabrück, archaeologists have found the remains of a turf wall2 built along a narrow passage, from behind which the Germans struck the column. The legions were wiped out, and Rome gave up its plan for a province reaching to the Elbe.
3. Roncesvalles, 778: the rearguard in the pass
Returning from an expedition into Spain in August 778, Charlemagne's army crossed the Pyrenees in a long column. In a narrow pass, Basque fighters, whom Charlemagne's biographer Einhard calls Gascons, waited on the heights, fell on the rearguard and the baggage train3 and drove them down into the valley, where they were killed to a man. Einhard names among the dead the royal steward Eggihard, Anselm, count of the palace, and Roland, prefect of the Breton March3. The lightly armed attackers knew the ground and scattered before the Franks could strike back. Three centuries later the Song of Roland turned this raid into an epic battle against a vast Saracen army, the version most people know.
4. Hattin, 1187: a lure, not an ambush
Hattin is often called an ambush, but it is better described as a lure followed by an encirclement. Saladin attacked Tiberias to draw the army of the Kingdom of Jerusalem away from the springs where it was camped, then shadowed its march across waterless country with mounted archers, kept it from the water of the lake and set the dry scrub alight so that smoke blew into the Frankish ranks. On 4 July 1187 the exhausted army was trapped on the twin hill called the Horns of Hattin and destroyed. Saladin had not hidden his army; he had chosen the ground and let thirst do the rest.
5. Ain Jalut, 1260: the feigned retreat
When Hulegu withdrew most of his army east after the death of the Great Khan, he left a reduced Mongol force in Syria under his general Kitbuqa. The Mamluk sultan Qutuz marched out of Egypt to meet it. On 3 September 12604, near the spring of Ain Jalut in Galilee, the Mamluk vanguard under Baybars engaged the Mongols and then, according to the Mamluk chroniclers, fell back, drawing them toward the main Mamluk army waiting in the hills. The Mongols, masters of the feigned retreat themselves, were caught by it. After hard fighting their army broke and Kitbuqa was killed4. It was the first major Mongol defeat in the west that was never reversed.
6. Cajamarca, 1532: the trap in the square
On 16 November 1532 Francisco Pizarro and 168 Spaniards5 waited in the town of Cajamarca, deep inside the Inca Empire, for the emperor Atahualpa, who had just won a civil war and was camped nearby with a large army. Pizarro hid his horsemen, foot soldiers and a few small cannon in the long buildings around the main square. Atahualpa entered with thousands of attendants, largely unarmed, expecting a parley. At a signal the guns fired, the cavalry charged out, and the Spaniards cut their way to the royal litter and seized the emperor. Estimates of the Inca dead run into the thousands. It was less a battle than a trap, and the capture of a living god-king paralysed the empire.
7. Okehazama, 1560: the storm and the headquarters
In June 1560 Imagawa Yoshimoto, one of the most powerful lords of eastern Japan, marched west through the lands of the young Oda Nobunaga. His army is traditionally put at around 25,000 men and Nobunaga's at perhaps 2,000 to 3,000, though these figures come from later chronicles and estimates vary. In the traditional account, while Imagawa's forces were spread out and his headquarters had halted in a narrow valley, Nobunaga led a picked force through the hills and, under cover of a sudden thunderstorm, fell on the headquarters itself. Imagawa Yoshimoto was defeated and killed6, and his army fell apart. Strictly this was a surprise attack rather than an ambush, but it is Japan's classic example of a small force striking the head of a large one, and it launched Nobunaga's rise.
8. Pearl Harbor, 1941: a surprise attack, not an ambush
On the morning of 7 December 1941 aircraft from six Japanese carriers struck the US Pacific Fleet at its anchorage in Hawaii in two waves, before any declaration of war had been delivered. Warnings had been sent and radar had even picked up the incoming planes, but the base was not ready for an air attack. Battleship Row was devastated, 188 aircraft were destroyed and 2,403 Americans were killed7. Because the fleet was at anchor rather than on the move, this was a surprise attack, not an ambush in the strict sense. Its great failure was what it missed: the American carriers were at sea, and within six months they helped turn the tide at Midway.
9. The Tet Offensive, 1968: surprise everywhere at once
On the night of 30 to 31 January 1968, during the truce for the Vietnamese lunar new year, North Vietnamese and Viet Cong forces attacked more than 100 cities and towns8 across South Vietnam, including Saigon, where a team broke into the grounds of the US embassy. American and South Vietnamese commanders had expected an offensive, but not its timing or its scale. Militarily it failed: in most places the attacks were beaten back within days, Hue was retaken after nearly a month of street fighting, and the Viet Cong lost heavily. Politically it was a shock that turned much of American opinion against the war, making Tet the rare surprise attack that lost on the battlefield and still changed the outcome.
What makes an ambush work
The great ambushes share a pattern. The victim was on the move and confident, as Flaminius, Varus and Charlemagne's rearguard were. The attacker knew the ground better: a lakeshore in fog, a forest track between marsh and hill, a mountain pass. And the trap was sprung all at once, so the victims could never form the order that made them strong. Surprise attacks such as Pearl Harbor and Tet show the same principle on a larger scale, and its limit: surprise can win a day without winning a war.