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pohnpei397 eNotes educator| Certified Educator

Diocletian was an emperor of Rome.  He ruled from 284 to 305 CE.  Diocletian brought stability for a time to an empire that was in something of a state of disarray when he came to power.  Diocletian brought the Roman army under control and improved the security of the empire.  Perhaps his most important legacy is that he laid out policies that were to form the basis for the creation of the Eastern Roman Empire.  He did this mainly by splitting the empire into different parts, each of which would be ruled by a separate ruler, though he himself would be the overall ruler.  This empire came to be called the Byzantine Empire and it outlasted the Western Roman Empire by centuries.


loraaa | Student
Diocletian (Latin: Gaius Aurelius Valerius Diocletianus Augustus;[5][notes 1] c. 22 December 244[3] – 3 December 311[4]), was a Roman Emperor from 284 to 305. Born to a family of low status in the Roman province of Dalmatia, Diocletian rose through the ranks of the military to become 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' other surviving son, Carinus, but Diocletian defeated him in the Battle of the Margus. With his accession to power, Diocletian ended the Crisis of the Third Century. He appointed fellow officer Maximian Augustus his senior co-emperor in 285. He delegated further on 1 March 293, appointing Galerius and Constantius as Caesars, junior co-emperors. 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 favorable peace.