Historical Events Feb 8 Flavius Constantine becomes Co-Emperor as Emperor Constantius III of the Western Roman Empire with Honorius Mar 25 Friday at 12 PM - city of Venice founded Famous Weddings Jun 7 Aelia Eudocia Athenais of Athens marries Eastern Roman Emperor Theodosius II Famous People Who Died in 421 AD Sep 2 Flavius Constantine III, Emperor of Western Roman Empire, dies at about 51 420 AD History by Year 422 AD