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Roman Legion

Ancient
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The Roman legion was the largest military unit of the Roman army, composed of Roman citizens serving as legionaries. In the late Republic and much of the imperial period a legion was organized into ten cohorts of six centuries each, with a full-strength legion numbering around 4,800 legionaries, though Julius Caesar's own legions during his campaign in Gaul often numbered only around 3,500 men. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/

Facts
Disputed
Founded Year
107 BCE 1
The Roman legion as a standing professional formation is usually dated to the Marian reforms of 107 BC; earlier Republican legions existed as citizen levies raised for individual campaigns rather than permanent units, so an earlier founding date is defensible depending on which institution is meant.
Force Type
Standing citizen-levy heavy infantry army organized in cohorts and centuries (legions) 1
Country
Roman Republic 1
Force Type
Force Type (category)
Army 1
Roman Legion
Filter Results3 entries
Connections

Associated With

Devised and directed personally by the dictator Quintus Fabius Maximus Verrucosus rather than by the legion as an institution; contemporary opposition to it is recorded in the dissent below.

Source Wikipedia: Fabian strategy
Source Wikipedia: Gladius
Hasta, Weapons Systems
Source Wikipedia: Hastati
Pilum, Weapons Systems

The Roman Legion is the standing force that fought under this tactical system.

Source Wikipedia: Roman legion
Roman Onager, Weapons Systems

The onager, a single armed torsion catapult, was a Roman Legion siege weapon from the late Roman period onward

Doctrines Developed

Source Wikipedia: Roman legion

Fought In

Boudican Revolt, Wars

Roman legions under Gaius Suetonius Paulinus crushed Boudica's revolt in Roman Britain around AD 60-61

Roman legions under Vespasian and Titus suppressed the Great Jewish Revolt (First Jewish-Roman War, AD 66-73), destroying the Second Temple

First Punic War, Wars

Roman legions, backed by Rome's newly built navy, fought the First Punic War against Carthage from 264 to 241 BC

Gallic Wars, Wars
Source Wikipedia: Roman legion
Jugurthine War, Wars

Roman legions under Metellus and later Marius fought Jugurtha of Numidia in the 112-106 BC Jugurthine War

Mithridatic Wars, Wars

Roman legions under Sulla, Lucullus and Pompey fought Mithridates VI of Pontus across the three Mithridatic Wars, 89-63 BC

Roman legions fought the Parthian Empire across centuries of intermittent war, including Crassus's disastrous defeat at Carrhae

Samnite Wars, Wars

Roman legions fought the Samnites across the three Samnite Wars between 343 and 290 BC, securing Rome's control of central Italy

Third Punic War, Wars

Roman legions besieged and destroyed Carthage in the 149-146 BC Third Punic War

Roman legions under Crassus and Pompey suppressed Spartacus's slave revolt in the 73-71 BC Third Servile War

Operates

Source Wikipedia: Carroballista
Source Wikipedia: Corvus (boarding device)
Source Wikipedia: Gladius
Hasta, Weapons Systems
Source Wikipedia: Hasta (spear)
Source Wikipedia: Onager (weapon)
Pilum, Weapons Systems
Source Wikipedia: Pilum
Source Wikipedia: Onager (weapon)
Source Wikipedia: Roman Pugio
Source Wikipedia: Spatha

Practices

In the Other Atlases

Found In

Also in Geography Atlas: where this subject is found.

Source Wikipedia: Roman legionLead paragraph of the cited Wikipedia articletier 2
Quote, Lead paragraph of the cited Wikipedia article
During the Roman Republic the manipular legion comprised 4,200 infantry and 300 cavalry.
Sources
1. Wikipedia: Roman legion
Wikipedia
  • Article text
    During the Later Roman Empire, the legion was reduced in size to 1,000 to allow for easier provisioning and to expand the regions under surveillance. Numbers would also vary depending on casualties suffered during a campaign; Julius Caesar's legions during his campaign in Gaul often only had around 3,500 men.
  • Size section
  • Late Republic section
  • Fought In: Gallic Wars
  • Associated With: Roman Legion Tactics (Manipular and Cohort System)
View the Source
Wikidata: Roman Legion
Wikidata Q163323, class allow-list match (w-wdresolver-0926)
Wikipedia: Gladius
Wikipedia
  • Associated With: Gladius
  • Operates: Gladius, Infobox: used_by
    Celtiberians in service to Carthage during the Punic Wars Roman foot soldiers during the wars of the Roman Republic and Roman Empire
View the Source
Wikipedia: Fabian strategy
Wikipedia
  • Associated With: Fabian Strategy
  • Practices: Fabian Strategy, Lead
    After these disasters, the Romans gave full authority to Fabius Maximus as dictator.
View the Source
Wikipedia: Hastati
WikipediaAssociated With: Hasta, History and deployment, Camillan system
Quote, Associated With: Hasta, History and deployment, Camillan system
Hastati were armed with short spears, or hastae, up to 1.8 metres (6 ft) long, from which the soldiers acquired their name.
View the Source
Wikipedia: Pilum
WikipediaOperates: Pilum, Article text
Quote, Operates: Pilum, Article text
The pilum (Latin: [ˈpiːɫʊ̃]; pl.: pila) was a javelin commonly used by the Roman army in ancient times.
View the Source
Wikipedia: Hasta (spear)
WikipediaOperates: Hasta, Article text
Quote, Operates: Hasta, Article text
The hasta (pl.: hastae) was the spear carried by early Roman legionaries, for which the Roman soldiers known as hastati were named.
View the Source
Wikipedia: Spatha
Operates: Spatha, Article text
Quote, Operates: Spatha, Article text
The spatha was a weapon used by the cavalrymen, while the auxiliaries and legionaries of the infantry used the gladius instead.
View the Source
Wikipedia: Carroballista
Operates: Carroballista, Article text
Quote, Operates: Carroballista, Article text
It seems that the technical innovations introduced by the adoption of the cheiroballistra by the Roman army at the end of the 1st century AD made the use of the cart possible.
View the Source
Wikipedia: Roman Pugio
WikipediaOperates: Roman Pugio, Article text
Quote, Operates: Roman Pugio, Article text
Like other items of legionary equipment, the dagger underwent some changes during the first half of the 1st century AD.
View the Source
Wikipedia: Onager (weapon)
Wikipedia
  • Operates: Roman Onager, Article body
    One reason the onager may have become the Roman military's primary type of torsion catapult was because it was easier to produce and required less technical knowledge to operate.
  • Operates: Onager, Article body
    One reason the onager may have become the Roman military's primary type of torsion catapult was because it was easier to produce and required less technical knowledge to operate.
View the Source
Wikipedia: Corvus (boarding device)
WikipediaOperates: Corvus, Lead
Quote, Operates: Corvus, Lead
The corvus (Latin for "crow" or "raven") was a Roman ship-mounted boarding ramp or drawbridge for naval boarding, first introduced during the First Punic War in sea battles against Carthage.
View the Source
Wikipedia: Battle of Alesia
WikipediaPractices: Double-Wall Siege (Circumvallation and Contravallation), Lead
Quote, Practices: Double-Wall Siege (Circumvallation and Contravallation), Lead
It was the last major engagement between Gauls and Romans, and is considered one of Caesar's greatest military achievements and a classic example of siege warfare and investment; the Roman army built dual lines of fortifications-an inner wall to keep the besieged Gauls in, and an outer wall to keep the Gallic relief force out.
View the Source
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