The Principate

The Principate is the name of the era within the Roman Empire when only one man, the princeps, was ruler. It ran from Augustus to Diocletian, who split the Empire and began both the Tetrarchy and the second period of the Roman Empire, known as the ''Dominate. ''The emperors who reigned during the Principate are below.

Julio-Claudian Dynasty (27 BC -- 68 AD)

Augustus (27 BC -- 14 AD) Tiberius (14 AD -- 37 AD) Caligula (37 AD -- 41 AD) Claudius (41 AD -- 54 AD) Nero (54 AD -- 68 AD)

Year of the Four Emperors (69 AD) 

Galba (68 AD -- 69 AD) Otho (69 AD) Vitellius (69 AD)

Flavian Dynasty (69 AD -- 96 AD)

Vespasian (69 AD -- 79 AD) Titus (79 AD -- 81 AD) Domitian (81 AD -- 96 AD)

Nervan-Antonian Dynasty (The Five Good Emperors) (96 AD -- 192 AD)

Nerva (96 AD -- 98 AD) Trajan (98 AD -- 117 AD) Hadrian (117 AD -- 138 AD) Antoninus Pius (138 AD -- 161 AD) Marcus Aurelius (161 AD -- 180 AD) Lucius Verus (161 AD -- 169 AD) Avidus Cassius (175 AD) (Usurper) Commodus (177 AD -- 192 AD)

Year of the Five Emperors & Severan Dynasty (193 AD -- 235 AD)

Pertinax (193 AD) Didus Julianus (193 AD) Septimius Severus (193 AD -- 211 AD) Pescennius Niger (193 AD -- 194/5 AD) Clodius Albinus (193/5 AD -- 197 AD) Caracalla (198 AD -- 217 AD) Geta (209 AD -- 211 AD) Macrinus (217 AD -- 218 AD) Diadumenian (217 AD -- 218 AD) Elagabalus (218 AD -- 222 AD) Alexander Severus (222 AD -- 235 AD)

Rulers During the Crisis of the Third Century (235 AD -- 284 AD)

Maximinus Thrax (235 AD -- 238 AD) Gordian I (238 AD) Gordian II (238 AD) Pupienus (238 AD) Balbinus (238 AD) Gordian III (238 AD -- 244 AD) Sabinianus (248 AD) (Usurper) Philip the Arab (244 AD -- 249 AD) Pacatianus (248 AD) (Usurper) Iotapianus (248 AD -- 249 AD) (Usurper) Silbannacus (248 AD or 253 AD) (Usurper) Decius (249 AD -- 251 AD) Priscus (249 AD -- 252 AD) Licinianus (250 AD) (Usurper) Herennius Etruscus (251 AD) Hostilian (251 AD) Gallus (251 AD -- 253 AD) Volusianus (251 AD -- 253 AD) Aemilian (253 AD) Valerian (253 AD -- 260 AD) Gallienus (253 AD -- 268 AD) Saloninus (260 AD) Ingennuus (260 AD) (Usurper) Regalianus (260 AD) (Usurper) Macrianus Major (260 AD -- 261 AD) (Usurper) Macrianus Minor (260 AD -- 261 AD) (Usurper) Quietus (260 AD -- 261 AD) (Usurper) Mussius Aemilianus (260 AD -- 261/2 AD) (Usurper) Aureolus (268 AD) (Usurper) Claudius II Gothicus (268 AD -- 270 AD) Quintillus (270 AD) Aurelian (270 AD -- 275 AD) Septimius (271 AD) (Usurper) Tacitus (275 AD -- 276 AD) Florianus (276 AD) Probus (276 AD -- 282 AD) Julius Saturninus (280 AD) (Usurper) Proculus (280 AD) (Usurper) Bonosus (280 AD) (Usurper) Carus (282 AD -- 283 AD) Carinus (283 AD -- 285 AD) Numerian (283 AD -- 284 AD)

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