Editing Battle of the Milvian Bridge (section)

== Historical background ==
The underlying causes of the battle were the rivalries inherent in [[Diocletian]]'s [[Tetrarchy]]. After Diocletian stepped down on 1 May 305, his successors began to struggle for control of the Roman Empire almost immediately. Although Constantine was the son of the Western Emperor [[Constantius Chlorus|Constantius]], the Tetrarchic ideology did not necessarily provide for hereditary succession. When Constantius died on 25 July 306, his father's troops proclaimed Constantine as [[Augustus (honorific)|Augustus]] in [[Eboracum]] ([[York]]). In Rome, the favorite was Maxentius, the son of Constantius' imperial colleague [[Maximian]], who seized the title of emperor on 28 October 306. But whereas Constantine's claim was recognized by [[Galerius]], ruler of the Eastern provinces and the senior emperor in the Empire, Maxentius was treated as a usurper. Galerius, however, recognized Constantine as holding only the lesser imperial rank of Caesar. Galerius ordered his co-Augustus, [[Flavius Valerius Severus|Severus]], to put Maxentius down in early 307. Once Severus arrived in Italy, however, his army defected to Maxentius. Severus was captured, imprisoned, and executed. Galerius himself marched on Rome in the autumn, but failed to take the city.<ref>Timothy D. Barnes, ''Constantine and Eusebius'' (Cambridge, Massachusetts: Harvard University Press, 1981), 30–31.</ref> Constantine avoided conflict with both Maxentius and the Eastern emperors for most of this period.<ref>Barnes, 30; Odahl, 86–87.</ref>

By 312, however, Constantine and Maxentius were engaged in open hostility with one another, although they were brothers-in‑law through Constantine's marriage to [[Fausta]], sister of Maxentius. In the spring of 312, Constantine gathered an army of around 40,000 soldiers (although the ancient historian [[Zosimus (historian)|Zosimus]] "claimed, quite implausibly, that Constantine invaded Italy with 90,000 soldiers and 8,000 cavalry, and that Maxentius commanded an army of 170,000 soldiers and 18,000 cavalry, including 80,000 Italians and 40,000 [[Carthaginians]]")<ref>{{cite book |last=Van Dam |first=Raymond |date=2011 |title=Remembering Constantine at the Milvian Bridge |location=New York |publisher=Cambridge University Press |page=34 |isbn=978-1-107-09643-1}}</ref> and decided to oust Maxentius himself.<ref>Cowen, p. 19</ref> He easily overran northern Italy, winning two major battles: the first near [[Battle of Turin (312)|Turin]], the second at [[Battle of Verona (312)|Verona]], where the [[praetorian prefect]] [[Ruricius Pompeianus]], Maxentius' most senior general, was killed.<ref>Odahl, 101–104.</ref>