The Ottoman conquest of the Morea occurred in two phases, in 1458 and 1460, and marked the end of the Despotate of the Morea, one of the last remnants of the Byzantine Empire, which had been extinguished in the Fall of Constantinople in 1453.
The Despotate of the Morea had been founded as an autonomous appanage ruled by members of the Byzantine imperial Palaiologos dynasty. During the 14th and 15th centuries, it was the scene of the last flourishing of Byzantine culture, but in the 1420s it was repeatedly attacked by Ottoman raiders under Turahan Bey, and was reduced to a tributary vassal by Sultan Murad II in 1446. From 1449, it was ruled by the brothers Demetrios Palaiologos and Thomas Palaiologos, who were engaged in a constant rivalry with one another: they divided the Morea peninsula among themselves, and neglected the payment of tribute to the Sultan. Having lost his patience with the quarreling brothers, and determined to avoid the Morea being used as a springboard for a Western crusade against him following his capture of Constantinople, Sultan Mehmed II invaded the peninsula in May 1458. While part of his forces besieged the Acrocorinth, the rest ravaged the peninsula. After the fall of the Acrocorinth, the two Palaiologoi brothers capitulated. Acrocorinth, Thomas' capital, Patras, and much of the northern part of the peninsula came under direct Ottoman rule; the Palaiologoi were left as tributary rulers in the southern half, which included the Despotate's capital, Mystras.
As soon as the Sultan left, the quarrel between the two brothers resumed, with Demetrios moving to a pro-Ottoman stance and Thomas, who had lost most of his domain, increasingly looking for Western assistance. Thomas rose in revolt in January 1459, leading Demetrios to call for Ottoman assistance from the governors installed in the northern peninsula. Mehmed II tried to mediate between the brothers, but the civil war resumed soon after. Bolstered by Italian reinforcements, Thomas gained the upper hand; Demetrios withdrew to Monemvasia and sent envoys to beg the Sultan for his assistance, while Pope Pius II tried to rally Western support for an anti-Ottoman crusade at the Council of Mantua. In April 1460, Mehmed II led his second invasion of the Morea. He first secured the surrender of Demetrios and the remaining territories under the latter's control, including Mystras, before moving west to the lands held by Thomas, who fled to Corfu with his family. The last sources of resistance in the peninsula were subdued in July 1461, and the Morea became an Ottoman province. Ottoman rule would be challenged during the First Ottoman–Venetian War, which broke out in 1463, and in which the Republic of Venice would unsuccessfully attempt to capture the peninsula; and the remaining Venetian coastal strongholds would be gradually reduced by 1540. Apart from a period of Venetian rule in 1685–1715, the Morea would remain in Ottoman hands until the outbreak of the Greek War of Independence in 1821.
Background: the Despotate of the Morea and the Ottoman Empire
After the Fourth Crusade (1203–1204), the Morea (Peloponnese) peninsula in southern Greece was conquered by Western European Crusaders ('Franks') and became the Principality of Achaea. The Republic of Venice, which also claimed dominion over the Morea by virtue of the Partitio Romaniae, accommodated itself to the situation and kept for itself only the two strategic forts of Modon and Coron in Messenia, on the southwestern tip of the peninsula. Byzantine rule was restored over the southeastern part of the Morea, around the fortress of Mystras, in 1262, and gradually expanded into the interior, at the expense of Achaea. In 1349, the Byzantine province of the Morea became a semi-autonomous appanage under a prince with the title of despot, who led his own administration and tax system; after 1380 the Despotate of the Morea was held by younger sons of the ruling Palaiologos dynasty. Constant warfare and Turkish raids on the coast and the interior severely depopulated the Morte countryside; to combat the lack of manpower, the despots encouraged the settlement of large numbers of Albanian migrants in the peninsula. The despots also faced frequent opposition from the Moreote nobility, who resented the arrival and placement in high office of people from outside the peninsula by the despots, as well as the imposition of new taxes and the curtailment of their autonomy by the despots' administration.
First wave of Ottoman expansion and its impact on the Morea
Towards the end of the 14th century, the rapid expansion of the Ottoman Empire in the Balkans made the Ottomans a determining factor in Moreote politics. Already in 1387, the Ottoman general Evrenos Bey raided deep into the Morea, as far as the Venetian colonies of Modon and Coron. Despot Theodore I Palaiologos (r. 1383–1407) even swore vassalage to Sultan Murad I in the same year; and Theodore's quarrels with local magnates were used by Sultan Bayezid I to force him to hand over various fortresses in the Morea, whereupon Theodore broke off his vassalage. Further Ottoman raids followed in 1394–1395 and 1397, in which the Despot's army was defeated and the peninsula plundered. The mounting Ottoman threat led Theodore to sell the entire Despotate to the Knights Hospitaller in 1399, while the Venetians hoped to form a league of the Frankish and Byzantine rulers against the Ottoman threat, and fortify the peninsula at the Isthmus of Corinth by rebuilding the Hexamilion wall.
The Ottoman defeat at the Battle of Ankara in 1402 and the subsequent civil war of the Ottoman Interregnum removed the Ottoman threat for the immediate future, allowing Theodore to recover the Despotate from the Hospitallers in 1402–1404. In 1415–1416, Emperor Manuel II Palaiologos came to the Morea in person, refortifying the Hexamilion and imposing his authority over the local potentates; this was followed by a resurgence of Byzantine power in the peninsula, as Byzantine forces captured most of Messenia and threatened Patras. In the more peaceful period after 1402, the Despotate of the Morea prospered and saw a major flowering of late Byzantine culture; its capital, Mystras, attracted philosophers and scholars, and was endowed with numerous fine churches. Venice did not remain idle, either: in addition to northeastern fortresses of Nauplia and Argos, which it had acquired in 1388 and 1394 respectively, the Republic expanded its Messenian possessions by acquiring Pylos (Navarino or Port de Jonc) in 1423.
End of the Principality of Achaea and resurgence of the Ottoman threat
In 1429–1432, a concerted Byzantine campaign finally ended the Principality of Achaea: Despot Constantine Palaiologos (later to rule as the last Byzantine emperor) seized Patras, while his brother, Despot Thomas Palaiologos, through a combination of force and marriage diplomacy seized the possessions of the last Prince of Achaea, Centurione II Zaccaria, the baronies of Chalandritsa and Messenian Arcadia. Apart from the Venetian possessions, all of the Morea was again in Byzantine hands. These successes were precarious, as the Ottoman threat revived at the same time: in 1423 the semi-autonomous Ottoman ruler of Thessaly, Turahan Bey, launched a devastating raid into the Morea, breaching the Hexamilion wall with ease. Another Ottoman raid in 1425 carried off thousands of Greek and Albanian Moreotes into slavery, and in 1431 Turahan returned, once again overcoming the Hexamilion defences. As the historian John Van Antwerp Fine Jr. commented, for now "the Ottomans were out for plunder and to soften up the area. They were not yet conquering towns or annexing any territory. But the earlier fate of
Thessaly and that of most of Epirus in 1430-31 should have been a clear message to the Morea that its days were numbered."
In 1435, Despot Constantine tried to absorb the neighbouring Frankish Duchy of Athens, but his attempt faltered because the local barons preferred to become Ottoman vassals than risk expropriation at the hands of the Byzantines. The attempt was repeated in 1444, taking advantage of the Ottoman diversion north to face the Crusade of Varna: the Duke of Athens, Nerio II Acciaioli, recognized Byzantine suzerainty, and Constantine's forces marched on, restoring Byzantine rule up to southern Thessaly and the Vlach territories of the Pindus by the end of 1445. Following the defeat of the crusade, however, the Ottomans turned south again, and by November 1446 they stood once again before the Hexamilion; all Constantine's gains in Central Greece had been lost. The Venetians, angered because Constantine during his campaigns had captured the port of Vitrinitsa from them, refused any assistance. Negotiations failed, and the Ottomans attacked the Hexamilion. After two weeks, with the aid of artillery, the wall was stormed; the Moreote army disintegrated rather than confront them, and the Ottomans proceeded to lay waste to the Morea. Sixty thousand were carried off as slaves, and the Ottoman troops withdrew only after both Constantine and Thomas became vassals of the Sultan and promised not to rebuild the Hexamilion.
In January 1449, Constantine succeeded to the Byzantine throne in Constantinople and left the Morea, which was divided in two halves: Thomas kept the western half, while the younger Demetrios received the eastern half. The two brothers were practically strangers, having lived apart since early childhood; they quickly quarreled, not only over possession of the district of Skorta, but also on religious-ideological grounds: Thomas supported the union of the Byzantine Church with the Catholic Church, while Demetrios opposed it. The dispute led to open war, which lasted until Turahan Bey imposed a settlement on the two despots which left Skorta to Thomas but obliged him to hand over Kalamata and Messenia to Demetrios in exchange.
Mehmed II and the Despotate of the Morea
In 1451, a new Ottoman sultan, Mehmed II, came to the throne, and immediately began preparations for a final assault on Constantinople. In order to prevent the despots from assisting Constantinople, in October 1452, Turahan led a large force into the Morea, broke through the Hexamilion, crisscrossed the peninsula almost at will, and wintered there. The only Byzantine success was the defeat and capture of Turahan's son Ahmed by Matthew Palaiologos Asen.
The fall of Constantinople on 29 May 1453 had great repercussions in the Peloponnese, and at first the two despots prepared to flee to Italy, before Mehmed II informed them that they could remain in office as tributary vassals. In autumn, a rebellion broke out against the unpopular despots by the Albanian immigrants, although it also found support among the native Greeks, and spread quickly: Thomas and Demetrios found themselves besieged in their capitals, Patras and Mystras. The rebels called for Venetian assistance, and although this did not materialize—the Republic was loath to be dragged into a potential conflict with the Ottomans—this alarmed the Sultan.
As the Sultan's vassals, the despots called upon Ottoman aid; first Turahan's son Ömer and then Turahan himself campaigned in the Morea, putting down the revolt. Turahan advised the two despots to compose their differences and rule well, and then departed the peninsula. At the same time, the tribute owed the Sultan by the despots was raised further still to 10,000 or 12,000 gold ducats each, while some local magnates used the opportunity to become direct subjects of the Sultan, bypassing the despots. The erosion of the brothers' authority also meant that taxes were frequently withheld, leading to their inability to pay the new, higher tribute; by 1458 they owed three years' worth of tribute money.
Even when faced with this situation, the two despots kept up their dispute. Not only that, but the two brothers independently pursued separate designs to receive help from Western Europe: Thomas sent the scholar John Argyropoulos, while Demetrios sent Frankoulios Servopoulos. Married to Catherine Zaccaria, daughter of the last Prince of Achaea, and a pro-Unionist, Thomas was the more pro-Western of the two, whereas Demetrios increasingly took a pro-Ottoman stance, or at least preferred to not risk the status quo, especially since his entreaties with Western rulers proved fruitless. News of this activity nevertheless reached Mehmed II, who, in the words of the Byzantinist Donald Nicol, "was astonished at the behaviour of the Despots Thomas and Demetrios. They were his sworn vassals. He had gone out of his way to keep them in power. Yet as soon as his back was turned he heard that they were plotting with the Pope, with the Duke of Milan and with the King of France to draw the western world into a crusade."
According to the contemporary historian Kritoboulos of Imbros, when Mehmed II placed the despots before the choice of paying the owed tribute or surrendering the Morea to him, the despots collected the money but kept it for themselves, possibly in hopes of a Western intervention, encouraged by the presence of a Papal squadron under Ludovico Trevisan in the Aegean. These hopes were in vain: despite strenuous efforts, Pope Callixtus III failed to rally the Western princes for anti-Ottoman crusade, or even at securing sufficient funds and troops for the Albanian warlord Skenderbeg, who was resisting Ottoman incursions into Albania at the time.
Fall of the Morea
First Moreote campaign of Mehmed II (1458)
The despots' quarrels, infidelity, and inability to pay the promised tribute led Mehmed II to decide to campaign in the Morea. Preparations began in late 1457, and the Sultan set out at the head of his army from Adrianople in spring 1458. The Sultan stayed his march at Thessaly, to rest his army and, according to Kritoboulos, to give the despots time to send envoys and settle their affairs peacefully. In the event, only envoys from Thomas arrived, with 4,500 ducats, when the Ottoman army's scouts were already scouting the northern approaches to the Isthmus of Corinth.