Excerpts from Books and Wikipedia
"Historians now often talk about ‘the crisis’ of the third century CE. What they mean is the process by which, after the assassination of Commodus in 192 CE, the Augustan template collapsed. The number of emperors is one obvious sign of that. In the nearly 180 years between 14 and 192 CE – apart from the single brief interlude of civil war after the death of Nero, when there were three unsuccessful claimants to the throne – there were just fourteen emperors. In the hundred years between 193 and 293 CE there were more than seventy (the list is elastic depending on how many unmemorable co-emperors, usurpers or ‘pretenders’ you decide to include). But, more to the point, any attempts to keep the legions out of the process of making emperors dramatically failed. Almost all the men who claimed the throne in the middle of the third century CE did so with the backing of one army unit or another." [Beard: SPQR, Kindle, p. 530-31]
Caracalla grants citizenship to all men
Human Rights
212
Alexander Severus' assassination was a part of the Crisis of the Third Century
Government
235
Rome celebrates 1000 years with spectacular games but future is not bright
Government
248
Valerian orders Senate to take strong steps toward Christians
Religion
257
Sasanian Persians defeat Romans and capture Emperor Valerian at Edessa
War
260
Aurelian builds new temple to the sun god
Religion
274
Diocletian appoints Tetrarchy and persecutes Christians
Religion
293
Armenia converts to Christianity
Religion
300
Diocletian issues first edict against Christians
Religion
303
Galerius issues Edict of Toleration ending Diocletian persecutions of Christians
Religion
311
Constantine defeats Maxentius in Battle of the Milvian Bridge to the west of Rome
War
312
Constantine and Licinius in Edict of Milan declare end of religious persecution
Religion
313
Constantine reunites empire by defeating Lincinius, eastern emperor
War
324
Bishops at Council of Nicea rule on Arian controversy
Religion
325
Constantine founds Constantinople, new capital for the Eastern Roman Empire
Geography
330
Constantine builds Church of the Holy Sepulchre
Architecture
335
Constantius II becomes co-emperor & promotes Arian Christianity
Religion
337
Constans is murdered by his own generals
Government
350
Julian the Apostate rejects Christianity & promotes Neoplatonic Hellenism
Religion
360
Jovian reestablishes Christianity
Religion
363
Valens becomes emperor and promotes Arian Christianity
Religion
364
Valentinian I is considered the last great western emperors
Government
364
Visigoths defeat Valens at Battle of Adrianople
War
378
Theodosius I declares that Nicene Christianity is the official state church
Religion
380
Library of Alexandria (Serapeum) burned after decree to destroy pagan temples
Religion
391
Emperor Theodosius bans sacrifices and closes pagan temples
Religion
391
Theodosius I defeats Western Roman ruler Eugenius at the Battle of Frigidus River
War
394
After death of Theodosius, Roman Empire splits--never to be united again
Government
395
Alaric leads Visigoths in invasion of Greece
War
401
Visigoths sack Rome--first breach of walls in 800 years
War
410
Valentinian III's reign is marked by dismemberment of Western Empire
Government
424
Theodosius II rebuilds walls & appoints commission for Codex Theodosianus
Government
429
Vandals invade North Africa and build pirate kingdom
War
429
Marcian becomes emperor of Eastern Roman Empire
Government
450
Christian Armenia is subdued by Zoroastrian Persians in Battle of Bertanantz
War
451
Attila the Hun defeated at the Catalaunian Plains by Aetius (Battle of Chalons)
War
451
Libius Severus becomes emperor of Western Roman Empire
Government
461
Romulus Augustulus is the last Western Roman Emperor
Government
475
The Western Roman Empire falls after victory by the barbarian Odovacar
War
476