Ottoman conquest of the Morea

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.

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.

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.

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.

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.

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.

[1][2] 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.

[5][7] 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.

[18][19] 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.

[22] 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.

"[28] 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.

[36] 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.

[40] 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.

[41][42] 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.

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.

[45][52] 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.

[55] 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.

[57] 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.

Mehmed II considered attacking him there, but was dissuaded due to the necessity of first marching through the rough terrain of Laconia, which would make resupply difficult.

[63][64] The fortress, now led by Matthew Asen, who had entered it at night with seventy men and carrying supplies, repelled the Sultan's initial attacks Mehmed II redeployed his troops to blockade it instead, while sending detachments to raid the surrounding region.

[66][69] The Sultan carried off thousands of prisoners captured during his campaign, who were resettled in Constantinople and its suburbs, as part of Mehmed's efforts to restore his new capital to its former glory.

[73] As a result, medieval historians, followed by many modern ones, place the blame for the subsequent events on Thomas, and especially on the machinations of Nikephoros Loukanes, who is said to have counselled him to this move.

[81] Thomas also did not hesitate to attack his brother at the same time, and soon Demetrios' position was crumbling: several of his commanders began acting as de facto independent lords in the fortresses they governed.

[81] At some point, Demetrios is rumoured to have offered the remainder of his lands to the Sultan, in exchange for a minor lordship elsewhere in the Ottoman Empire, likely the islands of Lemnos and Imbros.

[81] The chaos became complete when the local Albanians raided the lands of both factions, and the Ottoman garrisons in the northeast followed suit, laying waste to Arcadia, the heartland of the Morea.

[83][87] As a result, Mehmed II abandoned the campaign against Uzun Hasan and instead turned his army south against the Morea, with the aim of directly incorporating the rest of the peninsula into his empire.

[90] Mehmed II spent four days at Mystras, ordering its fortifications strengthened and installing a garrison there, before moving on to conquer the remainder of the Morea, accompanied by Demetrios.

Urged by the Venetian authorities to leave, and with Mehmed II and his army approaching, Thomas set sail with his family for Corfu in July, taking the relics of Saint Andrew, patron of Patras, with him.

[95] The Sultan renewed his agreements with Venice regarding the various fortresses the Republic held in the area, while Zagan Pasha operated further north and conquered Kalavryta, Chlemoutsi, and Santameri.

[88] The sole fortress to escape capture was Monemvasia, whose inhabitants, on the advice of Thomas, placed themselves under the authority of the Pope, before submitting to Venice in 1464 hopes of greater security from the Ottomans.