the reign of the roman emperor diocletian was notable for
Diocletian Diocletian (/ˌdaɪ.əˈkliːʃən/; Latin: Gaius Aurelius Valerius Diocletianus Augustus), born Diocles (22 December 244–3 December 311),[3][5] was a Roman emperor from 284 to 305. Born to a family of low status in Dalmatia, Diocletian rose through the ranks of the military to become Roman cavalry commander to the Emperor Carus. After the deaths of Carus and his son Numerian on campaign in Persia, Diocletian was proclaimed emperor. The title was also claimed by Carus' surviving son, Carinus, but Diocletian defeated him in the Battle of the Margus. Diocletian's reign stabilized the empire and marks the end of the Crisis of the Third Century. He appointed fellow officer Maximian as Augustus, co-emperor, in 286. Diocletian reigned in the Eastern Empire, and Maximian reigned in the Western Empire. Diocletian delegated further on 1 March 293, appointing Galerius and Constantius as Caesars, junior co-emperors, under himself and Maximian respectively. Under this 'tetrarchy', or "rule of four", each emperor would rule over a quarter-division of the empire. Diocletian secured the empire's borders and purged it of all threats to his power. He defeated the Sarmatians and Carpi during several campaigns between 285 and 299, the Alamanni in 288, and usurpers in Egypt between 297 and 298. Galerius, aided by Diocletian, campaigned successfully against Sassanid Persia, the empire's traditional enemy. In 299 he sacked their capital, Ctesiphon. Diocletian led the subsequent negotiations and achieved a lasting and favourable peace.
Fall of the Western Roman Empire By convention, the Western Roman Empire is deemed to have ended on 4 September 476, when Odoacer deposed Romulus Augustulus and proclaimed himself ruler of Italy, but this convention is subject to many qualifications. In Roman constitutional theory, the Empire was still simply united under one emperor, implying no abandonment of territorial claims. In areas where the convulsions of the dying Empire had made organized self-defence legitimate, rump states continued under some form of Roman rule after 476. Julius Nepos still claimed to be Emperor of the West and controlled Dalmatia until his murder in 480. Syagrius son of Aegidius ruled the Domain of Soissons until his murder in 487.[214] The indigenous inhabitants of Mauretania developed kingdoms of their own, independent of the Vandals, with strong Roman traits. They again sought Imperial recognition with the reconquests of Justinian I, and they put up effective resistance to the Muslim conquest of the Maghreb.[215] While the civitates of Britannia sank into a level of material development inferior even to their pre-Roman Iron Age ancestors,[216] they maintained identifiably Roman traits for some time, and they continued to look to their own defence as Honorius had authorized.[217][218]