AD 364: Emperor Jovian died under mysterious circumstances (suspected of dying by inhaling poisonous fumes), Valentinian I was proclaimed Emperor by Roman officers in Nicaea. His brother, Valens, was made co-emperor.
AD 366: Emperor Valentinian I appoints Jovinus, his Master of the Horse (Magister Equitum), general of the army. He defeats the Alamanni in three successive battles, and pushes them out of Gaul.
AD 369: Spring – Emperor Valens crosses the Danube, and attacks the Gothic tribes (Greuthungi and Tervingi). Valens and Athanaric, the Gothic king, eventually sign a treaty.