Editing Constantius III (section)

{{short description|Roman emperor in 421}}
{{distinguish|Constantine III (Western Roman emperor)}}
{{Use dmy dates|date=September 2024}}
{{good article}}
{{Infobox royalty
| name         = Constantius III
| image        = Constantius III diptych.jpg
| image_size   =
| alt          = 
| caption      = Consular diptych of Constantius III
| succession   = [[Roman emperor]] in the [[Western Roman Empire|West]]
| moretext     = 
| regnal name  = [[Imperator]] [[Caesar (title)|Caesar]] [[Flavia gens#Later use|Flavius]] Constantius [[Augustus (title)|Augustus]]
| reign        = 8 February – 2 September 421 (with&nbsp;[[Honorius (emperor)|Honorius]])
| birth_name   = Constantius
| birth_date   = <!-- Unknown date -->
| birth_place  = [[Naissus]], [[Moesia]]
| death_date   = 2 September 421
| death_place  = [[Ravenna]], [[Roman Italy|Italia]]
| burial_place = 
| spouse       = [[Galla Placidia]]
| issue        = {{ubl|[[Justa Grata Honoria]]|[[Valentinian III]]}}
| dynasty      = [[Theodosian dynasty|Theodosian]] and [[Valentinian dynasty|Valentinian]]
| full name    = 
}}

'''Constantius III''' (died 2 September 421) was briefly [[Western Roman Empire|Western Roman emperor]] in 421, having earned the throne through his capability as a general under [[Honorius (emperor)|Honorius]]. By 411 he had achieved the rank of ''[[magister militum]]'', and in the same year he suppressed the revolt of the usurper [[Constantine III (Western Roman emperor)|Constantine III]]. Constantius went on to lead campaigns against various barbarian groups in Hispania and Gaul, recovering much of both for the Western Roman Empire. He married Honorius's sister [[Galla Placidia]] in 417, a sign of his ascendant status, and was proclaimed co-emperor by Honorius on 8 February 421. Constantius reigned for seven months before dying on 2 September 421.