Decimation (from Latin decimatio, "destruction of a tenth") was a form of military discipline in the army of ancient Rome in which every tenth man in a group was executed by members of his own cohort. It was used by senior commanders to punish units guilty of capital offences such as cowardice, mutiny, desertion, and insubordination.
Origin and Etymology
The term derives from the Latin decimatio, from decimus ("tenth"). In its original Roman context, it referred specifically to the selection by lot and execution of one in ten soldiers from a disgraced unit.
Historicity in the Roman Republic
The historicity of decimation during the early and middle Republic (c. 5th–2nd centuries BC) is questioned by modern scholarship. The historian Michael J. Taylor (2022) has argued that the punishment was never actually practiced during the 3rd and 2nd centuries BC and was instead a rhetorical construct that proclaimed theoretical powers that commanders no longer dared to exercise. The only recorded instance predating the middle Republic—that of Appius Claudius in 471 BC, reported by Livy—contains anachronistic elements suggesting ahistoricity.
The middle Republican writer Polybius (2nd century BC) describes the procedure in detail: a soldiers' assembly before the tribunes, the drawing of lots to select one-tenth of the men adjudged cowardly, and their execution by clubbing at the hands of their comrades. Survivors were further punished with barley rations instead of wheat and were required to bivouac outside the fortified camp. However, scholars such as Goldberg (2015) and Taylor (2022) note that the presence of other well-documented non-lethal punishments for cowardice (demotion, exile, pay deductions) and the legal extension of provocatio rights (protecting citizens from summary execution) suggest that decimation was not commonly practicable during this period.
Revival in the Late Republic
The first well-attested historical instance of decimation occurred in 72 BC, during the Third Servile War (the revolt of Spartacus), under the command of Marcus Licinius Crassus. A unit of approximately 500 men who had fled from battle was decimated, resulting in about 50 executions. Later claims by Appian that Crassus decimated two legions or his entire army are rejected by modern historians as exaggerations.
Taylor identifies three factors for this revival: (1) the genuine emergency posed by the slave revolt; (2) the precedent set by the Sullan regime for ignoring citizen provocatio rights; and (3) an elite antiquarian intellectual movement that may have suggested reviving an archaic punishment whose origins were by then unknown.
Subsequent instances occurred in the following decades:
- 49 BC: Julius Caesar applied decimation to a small group of 120 ringleaders of a mutiny.
- 44 BC: Mark Antony ordered targeted killings of centurions.
- 36 BC: Mark Antony decimated two cohorts after defeats against the Parthians, producing approximately 80 fatalities (Plutarch, Antony 39.7).
- 34 BC: Octavian used decimation against a unit that fled during his Illyrian campaign.
- c. AD 18–20: Lucius Apronius used it for defeats in Numidia.
- AD 69: Emperor Galba used it against soldiers who refused demotion to naval service.
After AD 69, the punishment fell out of use during the Principate. The emperor Macrinus (r. AD 217–218) instituted a less harsh variant, centesimatio (execution of every 100th man). The Eastern Roman Emperor Maurice (r. AD 582–602) explicitly forbade decimation in his Strategikon, arguing that it could lead to a collapse of morale and seriously deplete unit manpower.
Procedure
According to Polybius and other ancient sources, the procedure involved: the disgraced unit being assembled; lots being drawn to select every tenth man; the selected men being beaten to death with clubs (fustuarium) by their fellow soldiers; and the survivors being subjected to further punishments including barley rations and encampment outside the fortified perimeter.
Post-Classical Instances
Decimation was revived in various post-classical conflicts:
- 1577: The Huguenot garrison of Brouage, after surrendering to Royalist forces during the French Wars of Religion, was decimated by city officials at La Rochelle.
- 1632 (Thirty Years' War): Wallenstein ordered the decimation of von Sparr's cuirassier regiment after it fled at the Battle of Lützen.
- 1642 (Thirty Years' War): Colonel Madlo's cavalry regiment was decimated after fleeing at the Battle of Breitenfeld; 90 men were executed at Rokycany.
- 1866 (Paraguayan War): President Francisco Solano López ordered the decimation of the Paraguayan 10th Battalion after it fled at the Battle of Curuzu.
- 1914 (World War I): A company of Tunisian tirailleurs who refused an order to attack was decimated by order of the divisional commander, resulting in ten executions.
- 1915–1917 (World War I): Italian General Luigi Cadorna used decimation and summary executions for units that retreated without orders. At least five cases occurred, with about a dozen soldiers killed in each case. The most famous instance was the killing of 28 soldiers from the Catanzaro brigade on 16 July 1917.
- 1918–1919 (German Revolution): 29 men from the Volksmarinedivision were executed after appearing to receive discharge papers.
- Russian Civil War: Leon Trotsky twice ordered decimation by May 1920 for units that had retreated without orders on the Volga front.
- 1918 (Finnish Civil War): White troops executed approximately 80 captured Reds in the "Lottery of Huruslahti."
- 1938 (Spanish Civil War): 46 men of the Republican 84th Mixed Brigade were executed by firing squad at Mora de Rubielos.
Modern Usage
In English, the word "decimation" was first used to mean a tax of one-tenth (a tithe). Through semantic change beginning in the 17th century, it evolved to refer to any extreme reduction in population or force, or an overall sense of destruction and ruin—not strictly punitive in nature nor limited to a reduction by one-tenth. This broader usage has been criticized by some language experts, including Bryan A. Garner, H. W. Fowler, and the Lake Superior State University "Banished Words List" (2008), though the expanded meaning is now standard in modern English.
