Byzantine Empire

At a glance

Was the Byzantine Empire the Roman Empire?

Yes, in the eyes of everyone who lived in it. The Oxford Dictionary of Byzantium puts it plainly: "The Byz. themselves called their state the Roman Empire (basileia ton Rhomaion) rather than Byzantium, applying the name BYZANTION only to their capital." Their emperor was "emperor of the Romans", and the word for an ordinary subject was Rhomaios, Roman. When the Council of Florence proclaimed union with the Latin church in 1439, its decree was issued with the agreement of "John Palaeologus, illustrious emperor of the Romans".

The name "Byzantine" is a later invention. The same dictionary states that "Byzantium as a term for the state was introduced into scholarship only in the 16th C. by Hieronymus Wolf (1516-80)", a German humanist and librarian to the Fugger bankers of Augsburg. In 1557 Wolf published in Basel a Latin edition of the history of Niketas Choniates, and in the same year, with Anton Fugger's support, an edition of the chronicle of John Zonaras.

The story is not quite that simple. In 2019 Zuzana Černáková of the Slovak Academy of Sciences drew attention to the twelfth-century French romance Partonopeus de Blois, whose author already used the name "Byzantium" for the empire instead of "Greek" or "Constantinopolitan". She argues that this challenges the belief that the term has been used for the medieval state only since the sixteenth century.

This entry uses "Byzantine" by convention, without implying a break with Rome.

When was the Byzantine Empire founded?

There is no single founding date, because the empire was not founded: it grew out of the Roman Empire without any break. The Oxford Dictionary of Byzantium notes that "since there is no act formally proclaiming the inauguration of Byz., no revolution abolishing the 'ancient regime'", historians date its beginning in different ways. The usual starting point is the dedication of Constantinople. Constantine I founded the city in AD 324 on the site of the Greek city of Byzantion, and on 11 May 330 it was, in George Ostrogorsky's words, "solemnly inaugurated". The Oxford Dictionary of Byzantium stresses that it was at first "not so much a 'new capital' as an imperial residence and monument to the emperor's greatness"; only later did it become the permanent seat of the eastern emperors.

The centuries from AD 395 to the early 600s are covered in more detail in the separate entry on the Eastern Roman Empire. In brief: Justinian I, who reigned from 527 to 565, retook North Africa from the Vandals, had Roman law gathered into the Corpus Iuris Civilis, and rebuilt Hagia Sophia, whose new church was inaugurated on 27 December 537. The plague of 542, in the words of the Oxford Dictionary of Byzantium, "reduced the population", and the ruinous wars of the next century followed.

Other historians start "Byzantium" later, with Heraclius in the seventh century, when the empire lost its southern provinces for good. The border data behind this map follows that later break. It draws the Byzantine Empire only from AD 633 and the Eastern Roman Empire up to 632.

How did Heraclius save the empire from Persia?

Heraclius, the son of the exarch of Carthage, sailed from Africa with a fleet, overthrew the emperor Phokas and became emperor on 5 October AD 610, in the middle of a war with the Sasanian Empire of Persia. According to John Haldon, "in 614 Jerusalem itself was taken", the True Cross was carried off to Ctesiphon, and "in 616 Persian troops reached the Bosphorus". Egypt was occupied for about ten years.

In 626 the Avars besieged Constantinople while the Persian general Shahrbaraz camped across the Bosporus. "The attack on 7 Aug. failed", the Oxford Dictionary of Byzantium records, and both armies withdrew. Heraclius had meanwhile taken the war into Persia. Theophanes describes him at the battle near Nineveh in December 627 killing three Persian champions, one of whom struck him "with a spear, wounding his lip". Chosroes II was overthrown, peace followed, and on 21 March 630, in Haldon's account, the True Cross was returned to Jerusalem.

The victory did not last. Arab armies invaded Syria in AD 634 and crushed the Byzantines at the Yarmuk in 636. The Arab historian al-Baladhuri gives Heraclius a farewell line as he withdrew: "Peace unto thee, O Syria, and what an excellent country this is for the enemy!" Syria was lost in 636, Palestine in 638, Mesopotamia and Armenia in 639/40 and Egypt by 642, according to Haldon. The Rashidun Caliphate had taken the empire's richest provinces in under a decade.

How did Byzantium survive the Arab conquests?

By holding on to Anatolia, the sea and its capital. The empire of the 640s was smaller and poorer, but it did not fall. Heraclius' grandson Constans II even visited Rome in AD 663, where, Paul the Deacon records, he took the bronze tiles from the roof of the Pantheon and sent them to Constantinople.

North Africa held out longer than Syria or Egypt. Walter Kaegi's study shows that the Arab general Hassan ibn al-Nu'man took Carthage in AD 695/6; other accounts date this first capture to 697. A Byzantine fleet briefly retook the city, but was driven out, and Kaegi calls 698 "the final Muslim conquest of Carthage".

The first Arab "siege" of Constantinople. Theophanes describes an Arab fleet that fought off the city each summer "from the month of April until September" for seven years in the AD 670s. Haldon writes instead that the fleet "blockaded the city". Leslie Brubaker and Haldon also date it earlier, to "the blockades of the years 664-8"; Marek Jankowiak, as summarised by others, places the main attack in 667–669. The traditional 674–678 is uncertain.

Greek fire. It was in this war, according to Theophanes, that "Kallinikos, an architect from Helioupolis in Syria, took refuge with the Romans and manufactured a naval fire with which he kindled the ships of the Arabs and burnt them with their crews." The Oxford Dictionary of Byzantium describes the weapon as a liquid, most likely crude oil mixed with resin and sulphur, "heated and propelled by a pump (siphon) through a bronze tube". The formula was never divulged and is still unknown; even when the Bulgars captured a supply with its tubes, they could not use it.

The siege of AD 717–718. Leo III had seized the throne on 25 March 717 when the Umayyad general Maslama besieged the city by land and sea. Theophanes describes fire-ships, snow lasting "a hundred days", famine in the Arab camp and Bulgar attacks from the rear. The Arabs withdrew on 15 August 718. Brubaker and Haldon call the 150,000 dead claimed by Arab sources "certainly highly inflated", and conclude that this was "the last such attempts on the Byzantine capital".

What were the themes?

The themes (themata) were the military provinces of the middle Byzantine empire, each under a general, the strategos, who held both military and civil power. The Oxford Dictionary of Byzantium lists the earliest as Armeniakon, Opsikion, Anatolikon and Thrakesion. How they arose is long debated; the dictionary notes that "the etymology and origin of the term is under discussion".

• George Ostrogorsky argued that Heraclius created the themes as a deliberate reform, settling soldiers on land in return for service, and that the term existed by AD 622. The Oxford Dictionary of Byzantium records that "this theory has been rejected", following the work of Ralph-Johannes Lilie.
• John Haldon sees no single reform. After the Yarmuk the field armies withdrew into Anatolia and were billeted on its provinces from AD 636, a process "in all probability completed by the mid-640s". The army districts took their names from these forces; the Thracian army became a thema only after 680.
• Brubaker and Haldon (2011) go further: the thema as an administrative province, with settled soldiers and fiscal duties, took shape only under Nikephoros I (802–811).

What was Byzantine iconoclasm?

Iconoclasm ("image-breaking") was the dispute over whether icons could be venerated. For over a century, up to 843, emperors and councils opposed their veneration.

The traditional story. Leo III, the first emperor of the so-called Isaurian dynasty, was in fact born at Germanikeia in northern Syria, not in Isauria. Theophanes reports that in AD 726 an undersea volcano erupted between Thera and Therasia, throwing up "pumice stones as big as hills" across the Aegean. Leo, he says, took this as a sign of God's anger and "stirred up a more ruthless war on the holy and venerable icons". Later accounts add that soldiers removed the icon of Christ above the palace's Chalke gate, causing a riot, and that Leo issued an edict against images.

The revision. Brubaker and Haldon's study of the iconoclast era, c. AD 680–850, rejects much of this. "There is no reliable evidence for an imperial edict of Leo III condemning the use of holy images or ordering them to be removed." The Chalke story has no contemporary witness; "all the later accounts are romantic and propagandistic elaborations", and the council of 787, which heaped abuse on Leo, never mentions it. On this view the policy took firm shape only under Leo's son Constantine V.

The councils. Constantine V's council at Hieria in AD 754, whose decree speaks for "its 338 members", condemned every image "made out of any material and colour whatever by the evil art of painters". Under the empress Irene, the Second Council of Nicaea in 787 reversed this. It ruled that icons deserve "due salutation and honourable reverence", not "that true worship of faith (latreia) which pertains alone to the divine nature". Leo V revived iconoclasm in 815. After the emperor Theophilos died, his widow Theodora summoned a council on 11 March 843 that restored the icons for good.

Irene and Charlemagne. In 797 Irene had her son Constantine VI blinded, "thus becoming the first female Byz. autocrat", in the words of the Oxford Dictionary of Byzantium. Three years later, on 25 December AD 800, Pope Leo III crowned Charlemagne "emperor of the Romans in the church of the holy apostle Peter", in the words of Theophanes, who also reports a plan, never carried out, for Charlemagne to marry Irene. She was overthrown on 31 October 802.

Who ruled the Byzantine Empire?

There was no fixed law of succession: emperors crowned their sons as co-emperors, but generals and courtiers often seized the throne. The table lists the main dynasties after AD 610, with leading rulers; earlier emperors are in the Eastern Roman Empire entry linked above.

What was the Macedonian Renaissance?

The name historians give to the revival of learning, law and art under the Macedonian dynasty, which ruled from AD 867 to 1056. Its founder, Basil I, rose at court under Michael III and then had him murdered. Skylitzes records that Basil "acceded on 24 September" 867. The Oxford Dictionary of Byzantium warns that the sources portray Michael as dissolute largely "to justify Basil I's murder of Michael".

The Slav mission. In AD 863 Michael III sent the brothers Constantine (later called Cyril) and Methodios from Thessaloniki to Moravia, at the request of its ruler Rastislav. To prepare, Constantine "devised the Glagolitic alphabet and a literary language, Church Slavonic", according to the Oxford Dictionary of Byzantium. Glagolitic, not the later Cyrillic script that bears his name. Through this mission and the baptism of the Bulgarian ruler Boris, the First Bulgarian Empire entered the Byzantine cultural world.

Law. "On Christmas Day, 888," writes Anthony Kaldellis, Basil's son Leo VI "released a sixty-book edition in Greek of Justinian's Corpus Iuris Civilis, the Basilika". Leo also issued the Book of the Eparch, the rules for the guilds of Constantinople, dated about 895 by its translator Edwin Freshfield and 911/12 in one manuscript. Silk merchants were forbidden to sell purple cloth of the reserved dyes to foreigners, "so as to prevent exportation of these out of the Empire"; goldsmiths had to report anyone trying to sell precious objects to outsiders.

In 968 the Western envoy Liudprand of Cremona had five purple silks confiscated as he left, because such garments "are prohibited to all nations except to us Romans".

Constantine VII (913–959) had handbooks compiled on ceremony, foreign peoples and farming. His De administrando imperio describes the Rus' bringing their boats down the Dnieper past rapids named in "Russian and Slavonic"; the first was Essoupi, "Do not sleep!".

How did Byzantium shape Kievan Rus'?

Through war, trade, treaties and conversion. The Rus' first attacked Constantinople in AD 860 (see the Rus' attack of 860); the Russian Primary Chronicle records later campaigns and treaties.

• 907 and 911. The chronicle tells of a great attack by Oleg in AD 907, which no Greek source records; its translator Samuel Cross notes that some historians doubt it. The treaty that followed is better attested. Its text is dated "this second of September, in the year of Creation 6420 (911)"; the envoys include Karl, Ingjald and Farulf.
• 941 and 944/945. Igor attacked Constantinople in AD 941 and was beaten off with Greek fire. Cross dates the new treaty's negotiations before Romanos I's fall on 16 December 944 and its ratification perhaps after March 945.
• Olga. Igor's widow Olga was received by Constantine VII, who describes the ceremonies himself. Cross, following the weekdays given, argues for 957; Kaldellis dates the visit to 946 and says she agreed to be baptised then, "probably to flatter the court".
• Sviatoslav. Her son conquered much of Bulgaria, but the emperor John I Tzimiskes defeated him at Dorostolon in AD 971, where, in Kaldellis's summary, the Rus' "lost thousands, while the Romans' losses were in the hundreds".

The decisive bargain came in AD 987–989. Basil II, facing the rebel Bardas Phokas, obtained troops from Vladimir of Kyiv in return for his sister Anna, on condition that Vladimir be baptised. In the chronicle Anna laments: "It is as if I were setting out into captivity." Cross's notes place the negotiations in the winter of 987–988 and the fall of Kherson in 989; the chronicle dates Vladimir's baptism to 988, while Cross thinks it more likely took place in 989 or 990. The Oxford Dictionary of Byzantium records that Basil II organised the Varangians into a regiment "in 988, when some 6,000 were sent by Vladimir I". The Varangian Guard served the emperors for two centuries. Kievan Rus' took its Christianity and much of its church culture from Byzantium.

How large was the Byzantine Empire under Basil II?

The empire reached its greatest medieval extent at Basil II's death in 1025, from southern Italy across the Balkans to the Danube and through Anatolia to Armenia and northern Syria.

The reconquests. Under Romanos II the general Nikephoros Phokas took Crete from its Arab emirs, capturing Chandax "on 6 or 7 March, 961", in Kaldellis's words. As emperor (963–969) Nikephoros II took Cilicia, with Tarsus, in AD 965, and in October 969 his troops took Antioch.

Basil II and Bulgaria. Basil II (976–1025) fought rebel generals and then the Bulgarian state of Tsar Samuel, a war that Kaldellis says sources give thirty-five or forty years: "even if we count it from 986, it would still be the single longest war in Roman history". On 29 July 1014 Basil's general Nikephoros Xiphias outflanked Samuel's army at the Kleidion pass. Skylitzes, writing decades later, reports: "They say that the emperor blinded the prisoners, about fifteen thousand in number, with orders that one man for each hundred be left one eye so he could be their guide". Samuel died soon after. The scale is doubted. Catherine Holmes notes that "victory was almost certainly not this complete", since another Byzantine army had just been defeated; Georgios Theotokis suggests the figure came from an exaggerated victory bulletin. Paul Stephenson points out, however, that Skylitzes' contemporary Kekaumenos independently gives about 14,000. Bulgaria was annexed in 1018. According to Stephenson, the epithet "Bulgar-slayer" (Boulgaroktonos) is first found around 1200, in the history of Niketas Choniates.

How big was it? There is no single agreed figure. Rein Taagepera's estimates, as tabulated in the Oxford World History of Empire, give 1.35 million km² for 1025; Warren Treadgold's history of the empire gives 1,675,000 km² for the same year. The map's own peak of 2.3 million km² is not a historical maximum: it is the area the border data gives for 633, its first year, before the losses to the Arabs had been drawn in.

How many people lived in it? The Oxford Dictionary of Byzantium is blunt: "All attempts to provide a reliable estimate for the entire population of Byz. have failed." For the capital, the dictionary holds that Constantinople "could not have been larger than 400,000" even in the fifth and sixth centuries, while Ostrogorsky wrote that by the sixth century the figure "was well over half a million".

How rich was it? Basil left a full treasury. Michael Psellos, who wrote a generation later, says it reached "the grand total of 200,000 talents". Kaldellis reads the reported surplus as either "43.2 million nomismata (implausible) or 14.4 million … (more plausible)", stored in vaults Basil had built for it. Basil died in December 1025.

What happened at Manzikert in 1071?

The emperor Romanos IV Diogenes was defeated and captured by the Seljuk sultan Alp Arslan in August 1071, on the road between the fortress of Manzikert (Malazgirt) and Chliat (Ahlat) in the Armenian highlands. It is often called the battle that lost Anatolia; the sources are more complicated.

After Basil II emperors changed rapidly. The Turks of the Great Seljuk Empire raided the eastern provinces, and in 1064 Alp Arslan took Ani, annexed only twenty years before. Meanwhile, on 16 July 1054, the papal legate Humbert laid a bull on the altar of Hagia Sophia excommunicating the patriarch Michael Keroularios and his followers. The Oxford Dictionary of Byzantium stresses that the anathemas were aimed at the persons involved, "not to the churches at large". When Pope Urban II's legates came in 1089, the patriarchate declared that its files contained "no evidence of formal schism". In Italy, Bari fell to the Normans on 16 April 1071, "ending the imperial presence in southern Italy", in Kaldellis's words.

The Oxford Dictionary of Byzantium records the battle on 19 or 26 August; Kaldellis gives the final day as 26 August. Estimates of Romanos's army range from 200,000–400,000 in late Muslim sources to about 60,000 (Jean-Claude Cheynet). Michael Attaleiates, who was there, describes a rout, not a great clash. After a day's pursuit Romanos had the imperial banner turned round to lead his troops back to camp. "But when those soldiers who were far from the main body saw the imperial banner being turned around, they thought that the emperor had fallen in defeat." A cousin of the emperor's stepson, whom the dictionary names as Andronikos Doukas, spread the report and fled with his men; others followed. Romanos fought on and was taken.

Attaleiates records the exchange that followed. The sultan asked: "What would you have done if you yourself held me in your power like this?" Romanos answered: "Know that I would have inflicted much torture on your body." Alp Arslan replied: "But I will not imitate your severity and harshness."

The disaster came afterwards. The Oxford Dictionary of Byzantium concludes that the battle "was not such a great disaster as it is usually presented by modern historians. The Byz. had insignificant losses". Kaldellis calls it the worst military disaster "since the Yarmuk", yet "not costly in terms of lives". Its damage lay in what followed: it "kicked off a vicious civil war". Romanos, released after a treaty, found Michael VII proclaimed in his place; he surrendered on a promise of safety and was blinded at Kotyaion on 29 June 1072. "By the end of the decade," Kaldellis writes, "the Romans had lost control of Asia Minor, their heartland".

How did the Komnenoi restore the empire?

Alexios I Komnenos, a general, took Constantinople in April 1081 and founded a dynasty that ruled for a century.

The Normans and Venice. In 1081 the Norman Robert Guiscard invaded the Balkans. Alexios was defeated outside Dyrrachium (Durrës) in October 1081: "Thus did the Latins beat the Roman army", his daughter Anna Komnene wrote in the Alexiad. To win the Venetian fleet against the Normans, he granted Venice sweeping privileges: wharves on the Golden Horn and the right to trade throughout the empire without paying "even an obol, neither for customs nor for any other tax", as Anna puts it. The charter is usually dated 1082; Peter Frankopan has argued that it belongs to 1092. These rights underpinned the eastern trade of the Republic of Venice.

The Pechenegs and the coinage. On 29 April 1091 Alexios destroyed the nomadic Pechenegs, Anna's "Scythians", at Levounion. She claims "a whole nation … together with their wives and children was completely wiped out". In 1092 Alexios reformed the debased coinage; Michael Hendy describes "the abrupt reintroduction of a gold coinage of high purity (1092)", the coin later called the hyperpyron.

The First Crusade. Alexios I's appeal for Western troops in 1095 helped trigger the First Crusade, a far larger movement than he had asked for. In Fulcher of Chartres' version of Urban II's speech at Clermont, the pope told the knights that "your brethren who live in the east are in urgent need of your help". Anna Komnene says nothing of an appeal by her father; she credits the movement to Peter the Hermit, who "worked out a cunning plan" to preach a march to the Holy Sepulchre. Peter Frankopan argues that Alexios's request was the real starting point, that he and Urban coordinated the expedition, and that Bohemond's circle later wrote him out of the story.

John II and Manuel I. Alexios's son John II (1118–1143) led a campaign into Cilicia in 1137 that Ostrogorsky calls "a triumphal progress". Under his son Manuel I (1143–1180) relations with Venice broke down: on 12 March 1171 he had all the Venetians in the empire arrested and their property confiscated. On 17 September 1176 his army was defeated at Myriokephalon by the Turks of the Sultanate of Rum; Niketas Choniates reports that Manuel himself compared the defeat with Manzikert. Manuel died on 24 September 1180.

1182–1185. In 1182 Andronikos I Komnenos, seizing power from Manuel's child heir, "mounted a war against the Latins in the City", in Choniates' words, and the populace joined in. Choniates gives no number; William of Tyre wrote that "it is said that more than four thousand Latins" were sold into slavery. Andronikos fell in 1185 to Isaac II Angelos, whose wedding levy, Choniates says, provoked the rising of Peter and Asan that founded the Second Bulgarian Empire.

Why did the Fourth Crusade sack Constantinople in 1204?

Because a crusade bound for the Holy Land ran into debt, took on a Byzantine pretender's cause, and then turned on the city when he could not pay.

The debt. In 1201 the crusade's leaders contracted with Venice for a fleet. Geoffrey of Villehardouin, one of the envoys, records the price: "the sum total … 85,000 marks". Far fewer crusaders came than expected, and they could not pay. Villehardouin says 34,000 marks were still owed; Robert de Clari gives 36,000. Venice deferred the debt in return for help against Zara (Zadar), a Christian city. Then Alexios Angelos, son of the deposed Isaac II, offered rewards if the crusade restored his father. The fleet sailed for Constantinople; Alexios IV was crowned beside his father on 1 August 1203, but could not pay what he had promised. In January 1204 he was overthrown by Alexios V Doukas, and the crusaders attacked.

The sack. Villehardouin dates the capture to "the Monday after Palm Sunday (12th April 1204)", and the looting began the next day. "Never, since the world was created, had so much booty been won in any city," Villehardouin wrote. He records that the pilgrims paid the Venetians 50,000 marks from their share and divided "at least one hundred thousand marks" among themselves, and that without the theft and the Venetian share there would have been at least four hundred thousand marks of silver. The total of 900,000 marks often quoted online does not appear in his account. Niketas Choniates, who lived through the sack, describes Hagia Sophia's altar broken up and mules led into the sanctuary to carry off its silver, and calls the crusaders "forerunners of Antichrist". On 16 May 1204 Count Baldwin of Flanders was crowned emperor of the new Latin Empire.

Was it planned? Jonathan Harris's survey of the debate (2004) shows how the answers have changed. Villehardouin presented a series of accidents; nineteenth-century historians proposed a Venetian plot, until Gabriel Hanotaux showed in 1877 that its key document, a supposed Venetian treaty with Egypt of 1202, was later. Many modern historians returned to accidents; Michael Angold described "a thousand or more decisions, often at cross-purposes". Harris himself argues that the diversion was "neither an intricate plot formulated by Venice nor the entirely unforeseen result of a series of errors or accidents", but grew out of a Western strategy after 1187 of using Byzantine wealth to finance the recovery of Jerusalem. He adds that the empire "may well have broken up of its own accord".

What did the Pope do? Innocent III had forbidden the crusaders, "under threat of excommunication, to invade or dare to harm the lands of Christians", unless they hindered the journey or there was some other just cause. After the sack he rebuked his legate for attending "not to the capture of the Empire of Constantinople, but rather to the defense of what is left of the Holy Land". As his anger subsided, however, he accepted the new Latin Empire. In 2001 Pope John Paul II said in Athens that the fact that the attackers were Latin Christians "fills Catholics with deep regret"; in 2004 he told Patriarch Bartholomew I that Catholics shared "the same indignation and sorrow that Pope Innocent III expressed". These were expressions of regret rather than a formal apology.

How did the Byzantine Empire end?

Exile and recovery. After 1204 three Greek states claimed the Byzantine succession: the Empire of Nicaea in western Anatolia under Theodore I Laskaris, the Despotate of Epirus in north-western Greece, and the Empire of Trebizond on the Black Sea. Nicaea proved strongest. In 1261 its general Alexios Strategopoulos, with "around 800 Roman and Cuman soldiers" according to the Foundation of the Hellenic World's encyclopaedia of Constantinople, found the Venetian fleet away and, in Ostrogorsky's words, "captured it at dawn on 25 July 1261 almost without any opposition". Baldwin II fled by ship; Michael VIII Palaiologos entered on 15 August.

Map note: the border data leaves the empire undrawn from 1227 to 1278, which does not match 1204–1261.

The Palaiologan centuries. Michael VIII accepted union with Rome at the Second Council of Lyon in 1274. Under his successors the Catalan Company, hired in 1303, turned on its employers, and what Ostrogorsky calls "the period of civil wars" in the fourteenth century ruined the state. John VI Kantakouzenos entered Constantinople in February 1347, the year the Black Death arrived "from southern Russia", as he recorded. In 1354 the Ottoman Turks occupied Gallipoli, their first foothold in Europe. The Serbian Empire had grown at Byzantium's expense; after the Ottomans crushed the Serbs on the Maritsa on 26 September 1371, "Macedonia lost its independence" (Ostrogorsky).

The empire shrank to Constantinople, Thessaloniki, a few islands and the Morea in the Peloponnese. A Latin text of 1437 quoted by Kaldellis puts the City's population at 40,000. In 1393 or 1395 the patriarch Antony IV wrote to the grand prince of Moscow that "it is impossible for Christians to have a church and no empire". Manuel II left on 10 December 1399 to seek help in the West. Relief came instead from Timur, who captured the sultan Bayezid I at Ankara on 28 July 1402. The Ottomans recovered; Murad II took Thessaloniki on 29 March 1430. John VIII accepted union again at Florence on 6 July 1439 ("the wall that divided the western and the eastern church has been removed"), but, as Doukas's translator notes, it was "rejected by the masses". A crusade was destroyed at Varna on 10 November 1444.

The siege of 1453. Constantine XI, crowned in the Morea on 6 January 1449, faced Mehmed II, who in 1452 built the fortress of Rumeli Hisarı on the Bosporus. The emperor had the union proclaimed in Hagia Sophia on 12 November 1452 according to George Sphrantzes or on 12 December according to Doukas. Doukas reports the minister Loukas Notaras saying: "It would be better to see the turban of the Turks reigning in the center of the City than the Latin miter."

The Ottoman army arrived in early April 1453; the sources give 4, 5, 6 or 7 April for the start of the siege. Sphrantzes, who tallied a secret census for the emperor, counted "4,773 Greeks, as well as just about 200 foreigners". Edward Gibbon, citing the same man, gave 4,970 Romans and 2,000 foreigners; Ostrogorsky about 5,000 Greeks and 2,000 foreigners, including 700 Genoese under Giovanni Giustiniani Longo. Mehmed's cannon battered the land walls near the gate of St Romanos. On 22 April he had ships hauled overland behind Galata into the Golden Horn: seventy-two of them according to the Venetian Nicolò Barbaro, eighty according to Doukas.

The final assault came before dawn on 29 May. Barbaro records that Giustiniani left his post and the Turks broke in "at the San Romano gate"; Doukas says Giustiniani was mortally wounded. Doukas alone adds that a small sally-port, the Kerkoporta, had been opened, and that "some fifty of the tyrant's renowned slaves leaped inside". The Greek historian Kritovoulos reported nearly four thousand dead and more than fifty thousand prisoners.

How Constantine XI died is uncertain. Sphrantzes, who was elsewhere in the city, writes only that his master "was killed". Kritovoulos says that he "fell in gallant combat" with those around him. Doukas has him cry out, "Is there no one among the Christians who will take my head from me?", before being cut down unrecognised. Barbaro heard rumours that his body had been seen among the corpses, or that he had hanged himself. That he died fighting is the version of Doukas and Kritovoulos.

After the fall. Mehmed entered the city the same day and went to Hagia Sophia, which became a mosque. According to Doukas, he ordered 5,000 families from the provinces to settle in the city. The anti-unionist Gennadios Scholarios was appointed patriarch by the sultan. Mistra, capital of the Morea, surrendered on 29 May 1460; Trebizond capitulated in August 1461 (Magoulias) or September (Ostrogorsky). The Ottoman Empire had taken the empire's place.

Map note: the border data draws the empire until 1474, which corresponds to the Crimean principality of Theodoro (Mangup), taken by the Ottomans in 1475 and never ruled by the Palaiologoi.

What is the legacy of the Byzantine Empire?

Its most visible legacy is Orthodox Christianity, with its liturgy and icons. Slavonic writing grew out of the mission of AD 863, and through Bulgaria and Rus' Orthodoxy reached much of Eastern Europe. The Basilika kept Justinian's law alive in Greek, and the patriarchate survived the conquest.

The "Third Rome". In Moscow the monk Filofei wrote in the 1520s that the church of Old Rome had fallen through heresy, and that "the grandsons of Hagar" had "hacked with axes" the doors of the church of the second Rome, Constantinople. This "Third Rome" idea is bound up with the rise of the Tsardom of Russia.

Hagia Sophia. Justinian's church remained a mosque until 1934, when it became a museum. In July 2020, the BBC reported, a Turkish court annulled its museum status and President Erdogan announced that Muslim prayers would be held there from 24 July; UNESCO said it "deeply regrets" the decision.

"Byzantine" as an insult. The picture of a devious, decadent Byzantium owes much to Enlightenment writers. In 1734 Montesquieu called the history of what he named the "Greek Empire" nothing but "un tissu de révoltes, de séditions & de perfidies", a fabric of revolts, seditions and treacheries. Edward Gibbon wrote that its annals "must continue to repeat a tedious and uniform tale of weakness and misery". Ostrogorsky, quoting both, wrote that there was "no need to emphasize the unsoundness" of that outlook.

Common myths about the Byzantine Empire

Timeline of the Byzantine Empire

What the map shows next

At 1025 on the map the empire is at its medieval height under Basil II, from southern Italy to Armenia. A century earlier it faced the First Bulgarian Empire across the Balkans. After 1204 the map shows Constantinople under the Latin Empire, with the Greek successor state of Nicaea in Anatolia. By 1453 the Ottoman Empire surrounds the last Byzantine lands, and from 1547 the Tsardom of Russia claims the Byzantine heritage.