Gaius Volusenus Quadratus (fl. mid-1st century BC) was a distinguished military officer of the Roman Republic. He served under Julius Caesar for ten years, during the Gallic Wars and the civil war of the 40s. Caesar praises him for his strategic sense and courageous integrity.
Military service 
In 55 BC Volusenus was sent out by Caesar in a single warship to undertake a week-long survey of the coast of south eastern Britain prior to Caesar's invasion. He probably examined the Kent coast between Hythe and Sandwich. When Caesar set off with his troops however he arrived at Dover and saw that landing would impossible. Instead he travelled north and landed on an open beach, probably near Walmer. Volusenus had evidently failed to find a suitable harbour, which would have prevented the damage Caesar's exposed ships would suffer at high tide. The great natural harbour at Richborough, a little further north, was used by Claudius in his invasion just 100 years later, but we do not know whether Volusenus travelled that far, or indeed whether it existed in a suitable form at that time (our knowledge of the geomorphology of the Wantsum Channel that created that haven is limited).
Volusenus later became Praefectus Equitum (cavalry commander). In 53 BC, during the revolt of Ambiorix, he was sent ahead by Caesar with cavalry to relieve Quintus Cicero, who was besieged by the Sugambri in Atuatuca, but found it difficult to convince the terrified defenders that the rest of Caesar's army was not far behind.
When the legate Titus Labienus suspected Commius, the formerly loyal king of the Atrebates, of conspiring against them in the winter of 54 or 53 BC, he invited him to a meeting and sent Volusenus and some centurions to execute him for his treachery. Commius escaped, but sustained a wound to the head.
In 51 BC Volusenus was serving as commander of cavalry under Mark Antony, and in the winter of that year was ordered by Antony to pursue Commius, who was conducting a campaign of agitation and guerrilla warfare. He defeated him in several skirmishes, and finally destroyed Commius's forces in a single engagement, although at the cost of a spear-wound to the thigh. S.P. Oakley sees this encounter as an unusual example of single combat in the Late Republic, echoing duels between Romans and physically superior Celts in the Early Republic. Commius himself escaped and later sued for peace on the condition that he never again had to meet a Roman.
In 48 BC, during the Civil War, an attempt to assassinate Volusenus was made by Aegus and Roscillus, two noble brothers of the Celtic Allobroges who had served in Caesar's cavalry throughout the Gallic Wars. The brothers had been caught defrauding their comrades of pay and decided to defect to Pompey's side. The death of Volusenus was meant to render Pompey useful service, but the task proved too difficult, and they were forced to defect without any such token.
Ronald Syme noted that Volusenus's decade-long tour of duty might have been uncommon for a man of his equestrian social rank, many of whom "owed their commissions less to merit than to the claims of friendship and influence or the hope of procuring gain and political advancement." The exemplary career of Volusenus, like that of Decidius Saxa, indicates that even in the Late Republic an equestrian might choose to excel as a career officer rather than as a publican or businessman. Volusenus is one of only three ranking officers to whom Caesar ascribes the quality of virtus.
Political career? 
Based on a "hopelessly corrupt" reading of one of Cicero's speeches against Mark Antony, Volusenus was sometimes identified by 19th-century scholars as a tribune of the plebs in 43 BC. The passage, and Volusenus's documented loyalty to Caesar, was thus interpreted to mean that he was a supporter of Mark Antony, but two other manuscripts indicate that the proper noun is in fact a verb (voluissent) and neither Cicero nor any other source mentions Volusenus among Antony's followers. T.R.S. Broughton does not record a plebeian tribunate for Volusenus in The Magistrates of the Roman Republic, confirming only that Volusenus was a military tribune in 56 and held the rank of praefectus equitum in 52–51 and again in 48.
Italian origin 
- Vir consilii magni et virtutis (Bellum Gallicum 3.5.2).
- Julius Caesar, Commentarii de Bello Gallico 3.5
- Commentarii de Bello Gallico 4.21
- Commentarii de Bello Gallico 6.41
- Commentarii de Bello Gallico 8.23
- Like those in which T. Manlius Torquatus and M. Valerius Corvus earned their respective cognomina; S.P. Oakley, "Single Combat in the Roman Republic," Classical Quarterly 35 (1985), p. 396.
- Commentarii de Bello Gallico 8.48
- Julius Caesar, Commentarii de Bello Civili 3.59-61
- Ronald Syme, The Roman Revolution (Oxford University Press, 1939, reissued 2002), pp. 70–71 online and 355.
- The other two are Quintus Cicero and Titus Labienus; Myles Anthony McDonnell, Roman manliness: virtus and the Roman Republic (Cambridge University Press, 2006), p. 308 online.
- John R. King, The Fourteen Philippic Orations of Marcus Tullius Cicero (Oxford, 1878), p. 262 online.
- Cicero, Philippics 14.3.
- Orelli conjectured that the passage should read alii praetorem, tribunum Volusienum, ego. "It has been assumed that this man is C. Volusenus Quadratus … but this is mere guessing," notes George Long, M. Tullii Ciceronis orationes (London, 1858), vol. 4, p. 704 online.
- John Richard King, The Philippic Orations of Marcus Tullius Cicero (Oxford: Clarendon Press, 1878, 2nd ed.), p. 336 online.
- Caesar, Bellum Gallicum 3.5.2.
- Aulus Hirtius, Bellum Gallicum 8.48; Cassius Dio 40.43.1.
- Broughton reassessed Volusenus's career in light of Syme's observations (see above) for the publication of volume 3 of The Magistrates of the Roman Republic (Atlanta: Scholars Press, 1984), p. 224. See also MRR2 (1952), pp. 212, 239, 246 (where the nomen is incorrectly given as Volusius), and 284. Broughton originally had counted the Volusenus who was tribune in 56 and the prefect Volusenus Quadratus as two different men. He excludes the vexed passage in the Phillippics.
- Elizabeth Rawson, Roman Culture and Society: Collected Papers (Clarendon Press, 1991), p. 321.