Portrait head of Constans on a coloured marble bust
Possible head of Constans set in a modern bust (Louvre)[1]
Roman emperor
Augustus9 September 337 –
January 350
PredecessorConstantine I
SuccessorMagnentius and Vetranio
Caesar25 December 333 – 9 September 337
Born322 or 323
DiedJanuary 350 (aged 27)[2]
Vicus Helena, southwestern Gaul
Flavius Julius Constans[2]
Regnal name
Imperator Caesar Flavius Julius Constans Augustus
FatherConstantine I
ReligionNicene Christianity

Flavius Julius Constans (c. 323 – 350), sometimes called Constans I, was Roman emperor from 337 to 350. He held the imperial rank of caesar from 333, and was the youngest son of Constantine the Great.

After his father's death, he was made augustus alongside his brothers in September 337. Constans was given the administration of the praetorian prefectures of Italy, Illyricum, and Africa.[3] He defeated the Sarmatians in a campaign shortly afterwards.[3] Quarrels over the sharing of power led to a civil war with his eldest brother and co-emperor Constantine II, who invaded Italy in 340 and was killed in battle by Constans's forces near Aquileia.[3] Constans gained from him the praetorian prefecture of Gaul.[3] Thereafter there were tensions with his remaining brother and co-augustus Constantius II (r. 337–361), including over the exiled bishop Athanasius of Alexandria,[3] who in turn eulogized Constans as "the most pious Augustus... of blessed and everlasting memory."[4] In the following years he campaigned against the Franks, and in 343 he visited Roman Britain,[3] the last legitimate emperor to do so.[5]

In January 350, Magnentius (r. 350–353) the commander of the Jovians and Herculians, a corps in the Roman army, was acclaimed augustus at Augustodunum (Autun) with the support of Marcellinus, the comes rei privatae.[6] Magnentius overthrew and killed Constans.[3][6] Surviving sources, possibly influenced by the propaganda of Magnentius's faction, accuse Constans of misrule and of homosexuality.[3]

Early life

Constans was probably born in 323.[2] He was the third and youngest son of Constantine I and Fausta, his father's second wife.[7] He was the grandson of both the augusti Constantius I and Maximian.[2] When he was born his father Constantine was the empire's senior augustus, and at war with his colleague and brother-in-law Licinius I (r. 308–324). At the time of Constans's birth, his eldest brother Constantine II and his half-brother Crispus, Constantine's first-born son, already held the rank of caesar. Constans's half-aunt Constantia, a daughter of Constantius I, was Licinius's wife and mother to another caesar, Licinius II.[8]

Constantine defeated and executed Licinius in 324.[8] In 326, Constans's mother Fausta was also put to death on Constantine's orders, as were Constans's half-brother Crispus and Licinius II. This left Constans's branch of the Constantinian dynasty – descended from Constantius I's relationship with Helena – in control of the imperial college.

According to the works of both Ausonius and Libanius he was educated at Constantinople under the tutelage of the poet Aemilius Magnus Arborius, who instructed him in Latin.[2]



On 25 December 333, his father Constantine I elevated Constans to the imperial rank of caesar at Constantinople.[2] He was nobilissimus caesar alongside his brothers Constantine II and Constantius II.[2] Constans became engaged to Olympias, the daughter of the praetorian prefect Ablabius, but the marriage never came to pass.[7] Official imagery was changed to accommodate an image of Constans as co-caesar beside his brothers and their father the augustus.[9]

It is possible that the occasion of Constans's elevation to the imperial college was timed to coincide with the celebration of the millennium of the city of Byzantium, whose re-foundation as Constantinople Constantine had begun the previous decade.[9] Byzantium was thought to have been founded in 667 BC, according to the reckoning derived from the Histories of Herodotus, and the Chronicon of Constantine's court historian Eusebius of Caesarea.[9] Rome had celebrated its own millennium in 248, in the reign of Philip the Arab, who may also have raised his son to co-augustus at the start of the anniversary year.[9]


Solidus of Constans marked: constans augustus.

After Constantine's death in 337, the army assassinated almost all of their male relatives.[10] Constans and his two brothers, Constantine II and Constantius II were proclaimed augusti and divided the Roman world among themselves on 9 September 337.[2] Almost immediately, Constans was required to deal with a Sarmatian invasion in late 337, in which he won a resounding victory.[7]

Division of the Empire among the Caesars appointed by Constantine I: from west to east, the territories of Constantine II, Constans, Dalmatius and Constantius II. After Dalmatius was killed his territory were divided between Constans and Constantius.

Constans managed to extract the prefecture of Illyricum and the diocese of Thrace, provinces that were originally to be ruled by his cousin Dalmatius, as per Constantine I's proposed division after his death.[11] Constantine II soon complained that he had not received the amount of territory that was his due as the eldest son.[12]

Gold medallion of Constans, equivalent to 9 solidi. Aquileia, 342 AD - Bode Museum

Annoyed that Constans had received Thrace and Macedonia after the death of Dalmatius, Constantine demanded that Constans hand over the African provinces, which he agreed to do in order to maintain a fragile peace.[12][13] Soon, however, they began quarreling over which parts of the African provinces belonged to Carthage and Constantine, and which parts belonged to Italy and Constans.[14] This led to growing tensions between the two brothers, which were only heightened by Constans finally coming of age and Constantine refusing to give up his guardianship. In 340 Constantine II invaded Italy.[13] Constans, at that time in Dacia, detached and sent a select and disciplined body of his Illyrian troops, stating that he would follow them in person with the remainder of his forces.[12] Constantine was eventually trapped at Aquileia, where he died, leaving Constans to inherit all of his brother's former territories – Hispania, Britannia and Gaul.[15]

Solidus of Constans marked: constans p·f· augustus on the obverse, with the emperor holding a vexillum with a chi-rho and crowned by Victory on the reverse, marked: spes rei publicae ("the hope of the Republic")

Constans began his reign in an energetic fashion.[15] In 341–342, he led a successful campaign against the Franks.[16] Eutropius wrote that he “had performed many gallant actions in the field, and had made himself feared by the army through the whole course of his life, though without exercising any extraordinary severity,”[15] while Ammianus Marcellinus remarked that Julian was the only person the Alamanni feared after the death of Constans.[16]

In the early months of 343, he visited Britain for unclear reasons.[7] Hunt argues against the theory of it being a military campaign, and instead suggests that it was for administrative purposes.[16]

Regarding religion, Constans was tolerant of Judaism and promulgated an edict banning pagan sacrifices in 341.[7] He suppressed Donatism in Africa and supported Nicene orthodoxy against Arianism, which was championed by his brother Constantius. Although Constans called the Council of Serdica in 343 to settle the conflict,[17] it was a complete failure,[18] and by 346 the two emperors were on the point of open warfare over the dispute.[19]


Surviving sources, possibly influenced by the propaganda of Magnentius's faction, accuse Constans of misrule and of homosexuality.[3][page needed] The Roman historian Eutropius says Constans "indulged in great vices," in reference to his homosexuality, and Aurelius Victor stated that Constans had a reputation for scandalous behaviour with "handsome barbarian hostages."[7][page needed] Nevertheless, Constans did sponsor a decree alongside Constantius II that ruled that "unnatural" sex should be punished meticulously. However, according to John Boswell, it was likely that Constans promulgated the legislation under pressure from Christian leaders, in an attempt to placate public outrage at his own perceived indecencies.[20][page needed]


Solidus of Constans

Court officials began plotting to overthrow Constans. Ancient sources assert that he was deeply unpopular,[21][22] and attribute his downfall to his own failings. He is accused of employing corrupt ministers[21][23] (one example being the magister officiorum Flavius Eugenius),[22] neglecting portions of the empire,[23][22] personal greed,[21][23][24] and treating his soldiers with contempt.[23][24]

On 18 January 350,[25] the general Magnentius declared himself emperor at Augustodunum (Autun) with the support of the troops on the Rhine frontier and, later, the western provinces of the Empire.[26] Constans was distracted by a hunting trip when he was notified of the elevation of Magnentius,[27] and he was forced to flee for his life. As he was trying to reach Hispania, supporters of Magnentius cornered him in a fortification in Helena (Elne) in the eastern Pyrenees of southwestern Gaul,[28] where he was killed after seeking sanctuary in a temple.[29] An alleged prophecy at his birth had said Constans would die "in the arms of his grandmother". His place of death happens to have been named after Helena, mother of Constantine and his own grandmother, thus realizing the prophecy.[30]

Family tree

See also: Constantinian dynasty

Family of Constans

Emperors are shown with a rounded-corner border with their dates as Augusti, names with a thicker border appear in both sections

1: Constantine's parents and half-siblings

HelenaFlavia Maximiana Theodora
  • Constantine I
  • 306–337
Flavius DalmatiusHannibalianusFlavia Julia Constantia
GallaJulius ConstantiusBasilinaLicinius IIEutropiaVirius Nepotianus
HannibalianusConstantinaConstantius Gallus

2: Constantine's children

  • Constantine I
  • 306–337
  • Constans
  • 337–350
HannibalianusConstantinaConstantius Gallus

See also


  1. ^ "L'empereru Constant Ier?". Louvre
  2. ^ a b c d e f g h Jones, Martindale & Morris, p. 220.
  3. ^ a b c d e f g h i Tougher, Shaun (2018), "Constans I", in Nicholson, Oliver (ed.), The Oxford Dictionary of Late Antiquity, Oxford University Press, doi:10.1093/acref/9780198662778.001.0001, ISBN 978-0-19-866277-8, retrieved 2 November 2020
  4. ^ Athanasius (2018), Atkinson, M. (ed.), Apologia ad Constantium, Christian Literature Publishing Co., retrieved 24 November 2023
  5. ^ Norwich, p. 81n
  6. ^ a b Tougher, Shaun (2018), Nicholson, Oliver (ed.), "Magnentius", The Oxford Dictionary of Late Antiquity, Oxford University Press, doi:10.1093/acref/9780198662778.001.0001, ISBN 978-0-19-866277-8, retrieved 2 November 2020
  7. ^ a b c d e f Michael DiMaio Jr. and Robert Frakes, Constans I (337-350 A.D.)
  8. ^ a b Pohlsander, Hans A. (1997). "Constantia (Wife of Licinius)". De Imperatoribus Romanis. Archived from the original on 4 March 2022.
  9. ^ a b c d Ramskold, Lars (2018). "The silver emissions of Constantine I from Constantinopolis, and the celebration of the millennium of Byzantion in 333/334 CE". Jahrbuch für Numismatik und Geldgeschichte. 68: 145–198. ISBN 978-3-943639-06-3.
  10. ^ Hunt 1998, p. 3.
  11. ^ Victor, 41:20
  12. ^ a b c Gibbon, Ch. 18
  13. ^ a b Victor, 41:21
  14. ^ Zosimus, 2:41-42
  15. ^ a b c Eutropius, 10:9
  16. ^ a b c Hunt 1998, p. 6.
  17. ^ Socrates Scholasticus, Church History, book 2, chapter 20.
  18. ^ Catholic Encyclopedia, 1930, Patrick J. Healy, Sardica
  19. ^ "Council of Sardica | ancient ecclesiastical council | Britannica".
  20. ^ Boswell, John (1981). Christianity, Social Tolerance, and Homosexuality: Gay People in Western Europe from the Beginning of the Christian Era to the Fourteenth Century. Chicago: University of Chicago Press. ISBN 0-226-06711-4.
  21. ^ a b c Barnes 1993, p. 101.
  22. ^ a b c Hunt 1998, p. 10.
  23. ^ a b c d Harries 2012, p. 190.
  24. ^ a b Crawford 2016.
  25. ^ Jones, Martindale & Morris, p. 532.
  26. ^ Eutropius, 10:9:4
  27. ^ Harries 2012, p. 195.
  28. ^ Victor, 41:21:23
  29. ^ Gibbon, Edward (1900). The Decline and Fall of the Roman Empire. Vol. 2. P. F. Collier & Son. p. 117. Before he could reach a seaport in Spain, where he intended to embark, he was overtaken near Helena, at the foot of the Pyrenees, by a party of light cavalry, whose chief, regardless of the sanctity of a temple, executed his commission by the murder of the son of Constantine.
  30. ^ Cárdenas, Fabricio (2014). 66 petites histoires du Pays Catalan [66 Little Stories of Catalan Country] (in French). Perpignan: Ultima Necat. ISBN 978-2-36771-006-8. OCLC 893847466.


Primary sources

Secondary sources

Regnal titles Preceded byConstantine I Roman emperor 337–350 With: Constantius II and Constantine II Succeeded byMagnentiusVetranio Political offices Preceded byUrsusPolemius Roman consul 339 With: Constantius Augustus II Succeeded bySeptimius AcindynusL. Aradius Valerius Proculus Preceded byAntonius MarcellinusPetronius Probinus Roman consul II 342 With: Constantius Augustus III Succeeded byM. Furius PlacidusRomulus Preceded byAmantiusM. Nummius Albinus Roman consul III 346 With: Constantius Augustus IV Succeeded byVulcacius RufinusEusebius