Soon after the death of Hunyadi the long career of the Servian Prince Brankovitch came to an end, and with it closed the history of Servia as a vassal state, for his death was followed by long and bloody quarrels over the succession. Finally, the claim of Brankovitch’s daughter-in-law, Helena, the widow of his son Lazaras, was acknowledged. Her accession gave Mohammed an excuse for appearing as the champion of an Ottoman pretender. The Sultan’s influence over the Servian nobility was increased by the fact that Helena was favorable to the Latin Church; she placed Servia under the protection of the Pope, and married her daughter to the heir of the Bosnian kingdom. But this foreign help availed nothing. Many of the strong places in Servia were captured, including the city of Semandria (1459). The Servian “woiwodes,” who preferred the domination of the Sultan to the acceptance of the religion of Rome, showed themselves disloyal to Helena the younger, who was obliged to withdraw, to Hungary first, and then to Rome, where she died as a nun in 1474.
After the destruction of Servia, and its absorption by the Ottomans, came the turn of Bosnia, like Servia disturbed by disputes between vassal princes, which were taken advantage of by Mohammed. King Stephen’s pro-Roman policy made him unpopular among his nobles; therefore, when the Turk’s army appeared, there was no great difficulty in overrunning the country. The King retired in a panic from his strongly fortified capital, and while in flight was captured and afterwards executed (1464). Herzegovina, which still remained in Christian hands, could not resist the successful aggression of the Turks, and its occupation took place three years after the annexation of Bosnia. As Bosnia was a vassal state of Hungary, its King, Matthias, found himself obliged to look to the safety of his territories. Scanderbeg, who was alarmed at the taking of Herzegovina, and Venice, as the mistress of all the cities in the Morea, had just begun to realize the need of common action to protect their interests.
On the part of the Hungarians war was waged on a small scale, but the Venetians employed a celebrated condottiere, Bertoldo d’Este, to head an expedition of thirty-two galleys and other ships armed by many thousand warriors. After some initial successes, the aim of the expedition failed, because of the death of Bertoldo while he was besieging the Turkish garrison at Corinth. Hitherto the steady advance of the Turks towards the south had been furthered by the anarchy and divisions of the rival races, among which the Albanians and the Greeks showed the most vitality. In Athens the ducal Florentine line brought notoriety to its closing days by the romantic record of its last duchess, the wife of Nerio II, who, when left a widow with the guardianship of her young son, fell in love with Contarini, a Venetian officer in Naples. She promised to marry him if he would get rid of his wife. The condition was accepted, and the young officer, by marrying the duchess, became master of Athens. Those who had acknowledged the old duke as their overlord, resented the introduction of Venetian rule, and appealed to Mohammed to interfere. He bestowed the duchy on a member of the reigning Florentine house, Franco, who caused his aunt, the scandal-making duchess, to be imprisoned and afterwards murdered. The commission of this crime produced discontent, and the Sultan gave orders to one of his captains to take possession of Athens.
Mohammed himself took personal charge of the expedition of 1458, which was conducted with great cruelty. The Albanians were especially singled out for savage reprisals. When Tarsos fell, the Albanian soldiers taken captive were horribly tortured, and at the capitulation of Corinth the leader of the Albanian contingent was sawn asunder. A short respite was at first granted to the Greek princes, members of the house of Paleologi, who were closely allied with the last Emperor of Constantinople, but they were finally dispossessed, and by the year 1460 nothing of Greece was left in the hands of the Christian powers except four Venetian strongholds. But these were not to be spared longer.
In 1463 the Morea was ravaged by the Turkish army, and five hundred Venetian soldiers met death by being sawn apart. In 1467 the island of Eubœa was attacked by both Ottoman fleet and land forces simultaneously. Great preparation was made for the defense of the Venetian citadel, but the plans were spoiled by the incapacity of the commander of the Venetian fleet to defend the approach to the island from the sea. The besieged garrison showed great heroism, and even when they discovered that their leaders were preparing to betray them, they stoutly held out and inflicted severe losses on the Ottomans. For reasons which are inexplicable, the Venetian fleet made no attempt to break down the bridge which connected the island with the continent; the occupation of this passageway finally enabled the Janitschars to enter the city. Its heroic defender, Paolo Erizzo, met the fate of being sawn asunder, because, as a chronicle states, the Turks had promised to save his head but not his thighs.
This heavy blow to Venice stirred the republic to a series of energetic reprisals. With her allies, the Neapolitans and the Knights of Rhodes, and aided by the Pope, she carried the war into Asia Minor. The town of Smyrna was occupied by the Venetian fleet, and the Seldjouk emirates, always ready to rebel against the Ottomans, were encouraged to revolt. When Lepanto was successfully protected by the Venetian fleet, it was felt that Mohammed had at last encountered a power that was ready to contest the imperial ambitions of Ottoman rule. But that there was no sufficient ground for over-confidence appeared when a Turkish general, Omar-beg, invaded Friuli, and began to ravage territories in the immediate neighborhood of Venice. A Venetian general fell fighting the Turks on the banks of the Isonzo, and the citizens of the republic could see with their own eyes the work of the Turks, as they burnt the villages that lie between the Isonzo and the Taghliamento. Scutari, however, withstood two Turkish sieges, though Mohammed himself took part in the operations. Finally, in 1479, Venice, deserted by her allies, was willing to arrange terms of peace. These involved the cession of Lemnos and certain possessions in Albania; but more significant of her humiliation was the payment of a war indemnity of 100,000 ducats, and the agreement to give an annual tribute of 110,000, in return for which sacrifices certain commercial advantages were conceded by the Turks.
Interpreting the treaty in its strictest sense, Mohammed, after arranging a peace with Venice, occupied the Ionian Islands, and soon afterwards showed his contempt for the military powers of Western Europe by sending a fleet of 150 ships to Otranto in Apulia, a province of the kingdom of Naples. The town, entirely unprepared for such a raid, was taken in 1480; the garrison and the archbishop were put to death, and the neighboring country was organized as a Turkish province with its capital at Otranto, where a garrison of 5000 Turkish soldiers was left behind.
The alarm created by this feat of arms was instantaneous. The Italian cities united and soon expelled the Turks from the peninsula, rivaling their enemies in Asiatic deeds of cruelty. Mohammed could not prosecute the conquest of Italy, because his attention was necessarily divided by the troubled state of Turkish rule in Asia, where the Seldjouk principalities still claimed an autonomy which, on crucial matters, made them independent of the Sultan.
In the north of Anatolia, which was directly in the hands of the Ottomans, there still remained the Empire of Trebizond, governed by a Greek prince, David Comnenus. Part of his dominions, Sinope and Paphlagonia, were conquered in 1461, and then the last Emperor of Trebizond turned for help to his Turkoman ally, Hassan, ruler of Armenia and part of Persia. Mohammed struck at his foes rapidly. Marching on Erzeroum, he forced Hassan to sue for peace, and so the Greek Emperor was left to meet the Turks unaided. The city of Trebizond was effectively encircled by land and sea, and David was soon brought to surrender, and afterwards, with many members of his household, was put to death. Equally implacable was Mohammed to the Seldjoukian emirates. At the death of Ibrahim, the Prince of Karamania, the Sultan intervened, while seven claimants were disputing over the succession, and after several campaigns annexed the emirate. Hassan’s time soon came. Feeling the insecurity of his rule, he asked help of Rhodes and Venice, especially requesting to be furnished with artillery, by the aid of which so many of the Ottoman victories were won. Two hundred Italian gunners were sent in answer to his call. In 1472 he took the Ottoman town of Tokat, and sacked it. This act caused Mohammed to take up the war against him in person. The two armies met on July 26, 1473, at Outlouk-Bali, near Terdjan, where a decisive victory was won by the Sultan. All the prisoners taken were massacred. The Turkomans had no desire to contest further the predominance of Ottoman rule, which was now extended without question over both Karamania and Anatolia.
It must not be supposed, however, that Mohammed was always successful. Albania held out against him under the heroic leader Scanderbeg, whose earlier exploits have been already chronicled. His success against the Ottomans continued without a break. Even when a nephew proved disloyal and brought an army of 40,000 Turks into the land, he rose up and smote the invaders after the manner of his earlier years (1461). For a time afterward peace prevailed; then, during the Venetian war, he stood as an ally of the republic. His old antagonist Mohammed had another opportunity of testing the valor of the Albanian chieftain at a decisive defeat of the Turkish army under the walls of Croia in 1465. Two years later Scanderbeg died at the age of sixty-seven, and his death was followed by civil strife.