Constantine II, emperor of the western part of the Roman Empire (Britain, Gaul, the Rhine provinces and Iberia), crosses the Alps and attacks the army of his brother Constans I, emperor of the central part of the Roman Empire (Upper Danube, Italy and middle Africa). They clash at Aquileia in northern Italy. Constantine is killed in a skirmish by an ambush of Constans' troops.
Constans is left sole ruler of the Western part of the Roman Empire, with his other brother, Constantius II, emperor of the Eastern portion.
CopticChristianity is introduced into Ethiopia by the Syrian apostle Frumentius. He and his colleague Aedesius ware captured by Ethiopians a year or two ago, and have become civil servants at the Aksumite court of King Ezana. Ezana is impressed with Frumentius' teachings and converts to Christianity.[9][10] Frumentius becomes the first Bishop of Axum and encourages the Christian merchants present in the country to practise their faith openly.[10][11]
The Western Roman Emperor Constans I is in Britain, possibly in a military campaign against the Picts and Scots. The last visit to Britain by a legitimate emperor.[12]
Pope Julius I tries to unite the Western bishops against Arianism by convoking the Council of Serdica (later Sofia), which acknowledges the pope's supreme authority and grants him the right to judge cases involving the legal possession of episcopal sees, but only Western and Egyptian bishops attend, and Arianism remains strong.
The Eastern Roman Emperor Constantius II campaigns in eastern Mesopotamia, against the Sassanid Persians.
Battle of Singara: The Roman army under Constantius wins a close victory, at the strongly fortified city of Singara (Mesopotamia). His enemy, King Shapur II, is forced to lift the siege, and withdraw the Persian army.
Shapur II, for the second time, besieges the Roman fortress of Nisibis in eastern Mesopotamia, but is repulsed by forces under General Lucilianus.
Gye becomes king of the Korean kingdom of Baekje.[13]
By topic
Art
The making of a detail of Admonitions of the Imperial Instructress to Court Ladies (attributed to Gu Kaizhi and being from the Six Dynasties period) begins (approximate year) and is completed in 406. It is now kept at the British Museum, London.
Emperor Constans I uses his influence to secure the return of Athanasius. He is restored as Patriarch of Alexandria, and documents are compiled relating to his expulsion, under the title Apology Against the Arians.
Li Shi, ruler of Cheng Han, fails in his attempt to halt a Jin expedition under Huan Wen. He flees to the capital Chengdu and surrenders his forces. Emperor Jin Mudi spares his life and makes him a marquess.
^ abHunt, David (1998). "The successors of Constantine". In Averil Cameron & Peter Garnsey (eds.). The Cambridge Ancient History XIII: The Late Empire, A.D. 337–425. Cambridge University Press. pp. 6-7. ISBN0-521-30200-5
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