Ancient Rome

===Religion===
{{Main|Religion in ancient Rome|Roman mythology|Roman temple}}
{{Further|Constantine the Great and Christianity|State church of the Roman Empire}}
[[File:Pompeii - Casa dei Vettii - Ixion.jpg|thumb|Punishment of [[Ixion]]: in the center is [[Mercury (mythology)|Mercury]] holding the [[caduceus]] and on the right [[Juno (mythology)|Juno]] sits on her throne. Behind her [[Iris (mythology)|Iris]] stands and gestures. On the left is [[Vulcan (mythology)|Vulcan]] (blond figure) standing behind the wheel, manning it, with Ixion already tied to it. [[Nephele]] sits at Mercury's feet; a Roman fresco from the eastern wall of the [[triclinium]] in the [[House of the Vettii]], [[Pompeii]], [[Pompeian Styles|Fourth Style]] (60–79 AD).]]
Archaic [[Religion in ancient Rome|Roman religion]], at least concerning the gods, was made up not of written narratives, but rather of complex interrelations between gods and humans.{{Sfn|Matyszak|2003|page=24}} Unlike in [[Greek mythology]], the gods were not personified, but were vaguely defined sacred spirits called ''[[Numen|numina]]''. Romans also believed that every person, place or thing had its own ''[[genius (mythology)|genius]]'', or divine soul. During the [[Roman Republic]], [[Religion in ancient Rome|Roman religion]] was organised under a strict system of priestly offices, which were held by men of senatorial rank. The College of Pontifices was uppermost body in this hierarchy, and its chief priest, the ''[[Pontifex Maximus]]'', was the head of the state religion. [[Flamen]]s took care of the cults of various gods, while [[augur]]s were trusted with taking the [[auspice]]s. The [[Rex Sacrorum|sacred king]] took on the religious responsibilities of the deposed kings. In the Roman Empire, deceased emperors who had ruled well were deified by their successors and the Senate.<ref>{{Cite book |last=Edward Gibbon |url=https://books.google.com/books?id=HvIbFyM1s54C&pg=PA91 |title=The history of the decline and fall of the Roman Empire |publisher=printed for J.J. Tourneisen |year=1787 |page=91}}; {{Cite book |url=https://books.google.com/books?id=a75PAAAAMAAJ&pg=PA644 |title=The Encyclopedia Americana: A Library of Universal Knowledge |publisher=Encyclopedia Americana Corporation |year=1919 |page=644}}</ref> and the formalised [[Imperial cult (ancient Rome)|imperial cult]] became increasingly prominent.

As contact with the [[Ancient Greece|Greeks]] increased, the old [[Roman mythology|Roman gods]] became increasingly associated with [[List of Greek mythological figures|Greek gods]].{{Sfn|Willis|2000|pages=166–168}} Under the Empire, the Romans absorbed the mythologies of their conquered subjects, often leading to situations in which the temples and priests of traditional Italian deities existed side by side with those of foreign gods.{{Sfn|Willis|2000}}

Beginning with Emperor [[Nero]] in the 1st century AD, Roman official policy towards Christianity was negative, and at some point, being a Christian could be punishable by death. Under Emperor [[Diocletian]], the [[persecution of Christians]] reached its peak. However, it became an officially supported religion in the Roman state under Diocletian's successor, [[Constantine I]], with the signing of the [[Edict of Milan]] in 313, and quickly became dominant. All religions except Christianity were prohibited in 391&nbsp;AD by an edict of Emperor [[Theodosius I]].<ref>[http://www.roman-emperors.org/theo1.htm Theodosius I (379–395 AD)] by David Woods. De Imperatoribus Romanis. 2 February 1999. Retrieved 4 April 2007.</ref>