311 CE
On his deathbed, Emperor Galerius declares religious freedom and issues the Edict of Serdica, ending the Diocletianic Persecution of Christians in the eastern half of the Roman Empire. Galerius dies at age 51 from a gruesome disease, possibly colorectal cancer or Fournier gangrene. Disaster of Yongjia: Xiongnu soldiers led by Liu Cong conquer and pillage the Jin dynasty capital at Luoyang and capture Emperor Huai; 30,000 residents in the city are massacred.
Geopolitics & Diplomacy
- Fearing an alliance between Licinius and Constantine I, Maximinus forges a secret alliance with Emperor Maxentius.source
Conflict & Security
- July 13 – Disaster of Yongjia: Xiongnu soldiers led by Liu Cong conquer and pillage the Jin dynasty capital at Luoyang and capture Emperor Huai; 30,000 residents in the city are massacred.source
Religion & Belief
- April 30 – On his deathbed, Emperor Galerius declares religious freedom and issues the Edict of Serdica, ending the Diocletianic Persecution of Christians in the eastern half of the Roman Empire.source
- July 2 – Pope Miltiades succeeds Eusebius as the 32nd pope of Rome.source
- Maximinus recommences the persecution of Christians, having encouraged his subjects to petition him to do so.source
- The Donatist schism begins in the African Church.source
- Maximinus Daza and Licinius divide the Eastern Empire between themselves.source
Deaths
- April 23 – Sima Yue (or Yuanchao), Chinese prince and regentsource
- May 5 – Galerius dies at age 51 from a gruesome disease, possibly colorectal cancer or Fournier gangrene.source
- May 5 – Galerius, Roman emperor (b. c.258)source
- May 5 – Wang Yan, Chinese official and politician (b. 256)source
- October 7 – Gou Xi (or Daojiang), Chinese inspector and generalsource
- November 25 – Peter I, patriarch of Alexandriasource
- December 3 – Diocletian, Roman emperor (b. 244)source
- Wang Mi (or Zigu), Chinese general and rebel leadersource
- Domitius Alexander, Roman emperor and usupersource