The Roman Empire was one of the most influential civilizations in world history. Beginning with Augustus in 27 BCE and ending in the West with Romulus Augustulus in 476 CE, Roman emperors ruled vast territories spanning Europe, North Africa, and the Middle East.
This complete list of Roman emperors presents every emperor of the Roman Empire in chronological order. From the Julio-Claudian dynasty through the Crisis of the Third Century and the final rulers of the Western Roman Empire, these emperors shaped the course of ancient history.
Explore each emperor’s biography, reign, achievements, and historical significance through the NoteRef People Timeline.
Principate (27 BC – AD 284)
The Roman Empire is traditionally divided into two major periods: the Principate (27 BCE–284 CE), when emperors maintained the outward form of the Republic while holding real power, and the Dominate (284–476 CE), when emperors ruled more openly as absolute monarchs. Within these periods, dynasties rose and fell, often through military coups, assassination, or civil war. Understanding these groupings helps make sense of an empire that lasted, in some form, for over five centuries.
Julio-Claudian Dynasty (27 BC – AD 68)
The first imperial dynasty, founded by Julius Caesar’s adopted heir Augustus, set the template for Roman rule. These five emperors oversaw Rome’s transformation from a republic into a military monarchy, establishing the Rhine-Danube frontier, expanding the road network, and building iconic monuments that still stand today. The dynasty is remembered for both extraordinary talent — Augustus and Claudius — and notorious excess — Caligula and Nero. It ended when Nero was declared a public enemy by the Senate and took his own life.
1. Augustus (27 BCE–14 CE)
2. Tiberius (14–37)
3. Caligula (37–41)
4. Claudius (41–54)
5. Nero (54–68)
Year of the Four Emperors (68–69)
The death of Nero in 68 CE triggered a brief but violent succession crisis. For the first time, it became clear that an emperor could be made somewhere other than Rome — by the legions on the frontier. Four generals seized power in rapid succession within a single year, each backed by different armies. The chaos ended only when Vespasian, commander of the eastern legions, marched on Rome and founded a new dynasty. The year demonstrated both the fragility of imperial power and the decisive role of the military in Roman politics.
6. Galba (68–69)
7. Otho (69)
8. Vitellius (69)
Flavian Dynasty (69–96)
The Flavians restored stability after the chaos of 69 CE and gave Rome some of its most enduring monuments, including the Colosseum, completed under Titus in 80 CE. Vespasian rebuilt the treasury after years of civil war and projected an image of simple, soldierly competence. Titus, despite a reign of only two years, was beloved by the Roman people and oversaw relief efforts after the eruption of Vesuvius destroyed Pompeii. Domitian, the last Flavian, was an effective administrator but clashed bitterly with the Senate, and was ultimately assassinated in a palace conspiracy.
9. Vespasian (69–79)
10. Titus (79–81)
11. Domitian (81–96)
Nerva–Antonine Dynasty (96–192)
Widely considered the golden age of the Roman Empire, this period produced a century of relative peace and prosperity. The Pax Romana — a broader term encompassing the long stability from Augustus through Marcus Aurelius — reached its cultural and administrative peak here. Four of its emperors — Nerva, Trajan, Hadrian, and Antoninus Pius — were chosen through adoption rather than birth, selecting successors based on merit. The historian Edward Gibbon called this era the period in history when the condition of humanity was most prosperous, though modern historians note that this view reflects an elite, Roman-centered perspective that ignores the experience of slaves, conquered peoples, and provincial subjects. The dynasty ended with Commodus, a vain and erratic ruler who preferred gladiatorial combat to governance, and whose assassination plunged Rome back into crisis.
12. Nerva (96–98)
13. Trajan (98–117)
14. Hadrian (117–138)
15. Antoninus Pius (138–161)
16. Marcus Aurelius & Lucius Verus (161–169, co-emperors)
Marcus Aurelius and Lucius Verus ruled simultaneously as co-emperors from 161 CE — the first time Rome had two equal Augusti at once. Both entries below reflect this joint reign.
17. Lucius Verus (161–169)
18. Commodus (180–192)
Year of the Five Emperors & Severan Dynasty (193–235)
The murder of Commodus in 193 CE set off another succession war. Five claimants fought for the throne — Pertinax, Didius Julianus, Pescennius Niger, Clodius Albinus, and Septimius Severus — each backed by different legions, echoing the chaos of 69 CE but on a larger scale. Septimius Severus, commander of the Pannonian legions, emerged victorious after defeating both Niger in the East and Albinus in the West. He and his successors — notably Caracalla, who extended Roman citizenship to all free inhabitants of the empire — increasingly relied on the army for power and legitimacy. The dynasty weakened as emperors became more dependent on military favor, setting the stage for the catastrophic instability that followed.
19. Pertinax (193)
20. Didius Julianus (193)
21. Pescennius Niger (193–194)
22. Clodius Albinus (193–197)
23. Septimius Severus (193–211)
24. Caracalla (198–217)
25. Geta (209–212)
26. Macrinus (217–218)
27. Elagabalus (218–222)
28. Severus Alexander (222–235)
Crisis of the Third Century (235–284)
The half-century between 235 and 284 CE was the most turbulent in Roman history. Over fifty individuals claimed the title of emperor during this period, most dying violently within months of taking power. Invasions on multiple frontiers, devastating plagues, economic collapse, and the temporary breakup of the empire into three competing states — the legitimate Roman center, the breakaway Gallic Empire in the West, and the Palmyrene Empire in the East — brought Rome to the edge of dissolution. The emperors listed below include the recognized rulers of the central Roman state as well as the leaders of these breakaway empires, without whom the period cannot be understood. It finally ended when Diocletian — a soldier of Balkan origin with no aristocratic background — seized power and implemented sweeping reforms that transformed the empire’s structure entirely.
29. Maximinus Thrax (235–238)
30. Gordian I (238)
31. Gordian II (238)
32. Pupienus (238)
33. Balbinus (238)
34. Gordian III (238–244)
35. Philip the Arab (244–249)
36. Philip II (247–249)
37. Decius (249–251)
38. Herennius Etruscus (251)
39. Hostilian (251)
40. Trebonianus Gallus (251–253)
41. Volusianus (251–253)
42. Aemilian (253)
43. Valerian (253–260)
44. Gallienus (253–268)
Gallic Empire (260–274) — breakaway Western state
During Gallienus’s reign, a large portion of the Western provinces — Gaul, Britannia, and Hispania — broke away under a series of independent emperors. This Gallic Empire was not a foreign conquest but a Roman institution, with its own Senate, consuls, and imperial court at Augusta Treverorum (modern Trier). It was reintegrated into the empire by Aurelian in 274 CE.
45. Postumus (260–269)
46. Laelianus (269)
47. Marius (269)
48. Victorinus (269–271)
49. Tetricus I (271–274)
50. Tetricus II (273–274, co-emperor)
Palmyrene Empire (263–273) — breakaway Eastern state
In the East, the brilliant queen Zenobia ruled an empire stretching from Egypt to Anatolia in the name of her son Vaballathus. Like the Gallic Empire, it was a Roman institution in form, and its rulers styled themselves as Roman emperors. Aurelian defeated and captured Zenobia in 272–273 CE, restoring eastern control.
51. Odaenathus (263–268)
52. Vaballathus (268–273)
Central Roman emperors (resumed)
53. Claudius Gothicus (268–270)
54. Quintillus (270)
55. Aurelian (270–275)
56. Tacitus (275–276)
57. Florianus (276)
58. Probus (276–282)
59. Carus (282–283)
60. Carinus (283–285)
61. Numerian (283–284)
Dominate (284–476)
Tetrarchy and Constantinian Dynasty
Diocletian’s solution to the empire’s unmanageable size was radical: divide rule among four co-emperors (the Tetrarchy), two senior Augusti and two junior Caesars, each responsible for a region. The system stabilized the frontiers but collapsed after his abdication as his successors fought for sole power. That struggle produced no fewer than six simultaneous claimants at its peak. Constantine the Great emerged victorious, reunited the empire under one ruler, and made a decision that would define the next millennium of Western history — the legalization and patronage of Christianity. He also founded Constantinople as a second capital on the Bosphorus, a city that would outlast Rome by a thousand years. His successors attempted to hold together his legacy, with Julian briefly reversing course and attempting to restore traditional Roman religion before dying on campaign in Persia.
62. Diocletian (284–305)
63. Maximian (286–305, 306–308)
64. Constantius I Chlorus (305–306)
65. Galerius (305–311)
66. Severus II (306–307)
67. Maximinus Daia (308–313)
68. Maxentius (306–312)
69. Licinius (308–324)
70. Constantine the Great (306–337)
71. Crispus (317–326, co-emperor)
72. Constantine II (337–340)
73. Constans (337–350)
74. Constantius II (337–361)
75. Julian (361–363)
76. Jovian (363–364)
Valentinian and Theodosian Dynasties
By the late 4th century, the empire was routinely divided between co-emperors ruling East and West. The defining crisis of the era came in 376 CE, when the Visigoths, fleeing pressure from the Huns, were allowed to cross the Danube into Roman territory. Mistreated by Roman officials, they revolted and defeated and killed Emperor Valens at the Battle of Adrianople in 378 CE — a watershed moment that shattered the myth of Roman military invincibility. Theodosius I, the last emperor to rule both halves of the empire, made Christianity the official state religion in 380 CE and banned traditional Roman worship before his death in 395 CE. After Theodosius, the empire was permanently split between his two sons.
77. Valentinian I (364–375)
78. Valens (364–378)
79. Gratian (367–383)
80. Valentinian II (375–392)
81. Theodosius I (379–395)
82. Arcadius (395–408) — East
83. Honorius (395–423) — West
84. Theodosius II (402–450) — East
85. Valentinian III (425–455) — West
86. Marcian (450–457) — East
Final Western Emperors (455–476)
The last twenty years of the Western Roman Empire were a slow unraveling. By this point, real power lay not with the emperors but with barbarian generals — chiefly Ricimer, who installed and removed emperors at will. Most of these final rulers were short-lived figures with little authority beyond the walls of Ravenna, which had replaced Rome as the Western capital. The symbolic end came in 476 CE when the Germanic chieftain Odoacer deposed the teenager Romulus Augustulus — whose very name combined Rome’s legendary founder with its first emperor — and simply did not bother to appoint a successor. It is worth noting that the legitimate emperor Julius Nepos, deposed by a military coup the year before, continued to claim the throne from Dalmatia until his murder in 480 CE; Odoacer himself recognized Nepos as the rightful emperor, making the question of who was truly “last” a matter of ongoing historical debate. The Eastern Empire, ruled from Constantinople, would continue for another thousand years as the Byzantine Empire.
87. Petronius Maximus (455)
88. Avitus (455–456)
89. Majorian (457–461)
90. Libius Severus (461–465)
91. Anthemius (467–472)
92. Olybrius (472)
93. Glycerius (473–474)
94. Julius Nepos (474–475; legitimate claimant until 480)
95. Romulus Augustulus (475–476)
Explore Roman Emperors on the NoteRef People Timeline
Header photo by Maria Dolores Vazquez on Unsplash
