The Roman Empire had had a division of responsibility since Diocletian named a co-emperor in 286. The eastern and western halves each had an emperor and a deputy called a caesar. But with the death of Theodosius the Great in 395, the empire was divided into two fully independent states. His son Arcadius inherited the Eastern Roman Empire, with its capital at Constantinople. This had been called Byzantium until 330, and the eastern empire is usually called the Byzantine Empire.

With the accession of Heraclius in 610, the title used was Basileus, the classical Greek word for 'king', and Autocrator. Some of these emperors had junior partners or co-regents; for clarity I am not including them in the main list. Another problem is that many of them had surnames or epithets as well as regnal numbers, so Leo III and Leo the Isaurian are the same. This presents a problem deciding how to hardlink them. If you ever want to node any of these people and would prefer to see them referred to differently, please let me know.

  1. Arcadius 395-408
  2. Theodosius II 408-450
  3. Marcian 450-457
  4. Leo I the Thracian 457-474
  5. Leo II 474
  6. Zeno the Isaurian 474-475
  7. Basilicus 475-476
  8. Zeno the Isaurian again 476-491
  9. Anastasius I 491-518
  10. Justin I 518-527
  11. Justinian I the "Great" 527-565
    with his depredations the Dark Ages begin
  12. Justin II 565-578
  13. Tiberius II Constantine 578-582
  14. Maurice 582-602
  15. Phocas 602-610
  16. Heraclius 610-641
  17. Constantine III 641
  18. Heracleonas 641
  19. Constans II Pogonatus 641-668
  20. Constantine IV 668-685
  21. Justinian II Rhinotmetus 685-695
  22. Leontius 695-698
  23. Tiberius III (Apsimar) 698-705
  24. Justinian II Rhinotmetus again 705-711
  25. Philippicus (Bardanes) 711-713
  26. Anastasius II (Artemius) 713-715
  27. Theodosius III 715-717
  28. Leo III the Isaurian 717-741
  29. Constantine V Copronymus 741
  30. Artavasdus 741-743
  31. Constantine V Copronymus again 743-775
  32. Leo IV the Khazar 775-780
    Despite being called a Khazar, he was the son of Constantine V
  33. Constantine VI 780-797
  34. Empress Irene 797-802
  35. Nicephorus I 802-811
  36. Stauracius 811
  37. Michael I Rhangabe 811-813
  38. Leo V the Armenian 813-820
  39. Michael II the Amorian 820-829
  40. Theophilus 829-842
  41. Michael III the Drunkard 842-867
  42. Basil I the Macedonian 867-886
  43. Leo VI the Wise 886-912
  44. Alexander 912-913
  45. Constantine VII Porphyrogenitus 913-919
    His surname refers to porphyrogeniture, by which the succession fell to the first son born while his father was emperor (born to the purple).
  46. Romanus I Lecapenus 919-944
  47. Constantine VII Porphyrogenitus again 944-959
  48. Romanus II 959-963
  49. Basil II Bulgaroctonus 963
  50. Nicephorus II Phocas 963-969
  51. John I Tzimisces 969-976
  52. Basil II Bulgaroctonus again 976-1025
    the Bulgar-slayer
  53. Constantine VIII 1025-1028
  54. Romanus III Argyrus 1028-1034
  55. Michael IV the Paphlagonian 1034-1041
  56. Michael V Calaphates 1041-1042
  57. Empresses Zoë and Theodora 1042
    daughters of Constantine VIII; Zoë's husbands were Romanus III, Michael IV, and Constantine IX
  58. Constantine IX Monomachus 1042-1055
  59. Theodora again 1055-1056
  60. Michael VI Stratioticus 1056-1057
  61. Isaac I Comnenus 1057-1059
  62. Constantine X Ducas 1059-1067
  63. Empress Eudocia Macrembolitissa 1067-1068
  64. Romanus IV Diogenes 1068-1071
  65. Eudocia Macrembolitissa again 1071
  66. Michael VII Parapinaces 1071-1078
  67. Nicephorus III Botaniates 1078-1081
  68. Alexius I Comnenus 1081-1118
  69. John II 1118-1143
  70. Manuel I 1143-1180
  71. Alexius II 1180-1183
  72. Andronicus I 1183-1185
  73. Isaac II Angelus 1185-1195
  74. Alexius III 1195-1203
  75. Alexius IV 1203-1204
    with Isaac II restored as co-regent
  76. Alexius V Ducas (Murtzuphlus) 1204
  77. Theodore I Lascaris 1204-1222
    In 1204 Constantinople was taken by the Crusaders, who created the Latin Empire and the Empire of Thessalonica. The remnants of the Byzantine state held out in remote parts of Greece. Theodore I held the title of despot until 1208. At this time one branch of the Byzantine dynasty fled and founded the tiny Empire of Trebizond on the Black Sea.
  78. John III Vatatzes 1222-1254
  79. Theodore II Lascaris 1254-1258
  80. John IV 1258-1261
  81. Michael VIII Palaeologus 1261-1282
    retook Constantinople and restored the Byzantine Empire
  82. Andronicus II 1282-1328
  83. Andronicus III 1328-1341
  84. John V 1341-1347
    At this point the internecine strife gets so confused that I offer the next few as at most roughly right.
  85. John VI Cantacuzene 1347-1355
  86. John V again 1355-1376
  87. Andronicus IV 1376-1379
  88. John V again 1379-1390
  89. John VII 1390
  90. John V again 1390-1391
  91. Manuel II 1391-1425
  92. John VIII 1425-1448
  93. Constantine IX Palaeologus (Dragases) 1448-1453
The Seljuq Turks defeated the Byzantines at Manzikert in 1071 and occupied most of Anatolia (Asia Minor). In 1353 they crossed over and settled in Europe for the first time, and took Adrianople (now Edirne) in 1357. The last of Anatolia fell in 1390. The Turks besieged Constantinople for the first time in 1422. Their final victory came under Mehmet Fâtih (Mehmet the Conqueror) on 29 May 1453.