203
- Sextus Varius Atinus Bassianus is born. He will come to be known as Heliogabalus.
217
- April: Caracella is assassinated. Julia Maesa begins a revolt with the aim of putting Heliogabalus on the throne of Rome.
- May 16: Heliogabalus is named Marcus Aurelius Antoninus Augustus, Emperor of Rome.
- June 8: Marcellus Opellius Macrinus is defeated, leaving Heliogabalus‘ claim to the throne unchallenged.
221
- Julia Maesa begins working to replace Heliogabalus with Severus Alexander.
222
- March 11: Heliogabalus is executed when the Praetorian Guard revolt against him. Severus Alexander becomes emperor and launches a massive and successful smear campaign against his predecessor before attempting to erase him from history. Severus also banishes any men with male lovers from public life.
306
- Constantine becomes Rome’s first Christian emperor.