Just a few days ago, we marked the anniversary of the start of the Ottoman Empire’s famous Second Siege of Vienna. For those who may not know, the failed siege would become one of the defining moments in the history of the empire, as it was the last great push of Ottoman expansion into the west.

So, I’d like to tell you the story of this famous siege.

Although the reign of Sultan Mehmed IV (1648-1687) was overshadowed by eight years of instability, under the capable leadership of the Köprülü father-and-son grand viziers, the empire sought to regain its strength, drawing the attention of Europe. And for a while, it appeared as though the empire’s days of glory had returned.

When Köprülü Fazıl Ahmed Pasha died in 1676, he was succeeded as grand vizier by his brother-in-law and stepbrother, Merzifonlu Kara Mustafa Pasha. By this time, Sultan Mehmed IV had entrusted virtually all affairs of state to the grand vizier, preferring to devote himself to hunting, a pastime that earned him the epithet "Mehmed the Hunter.”

Kara Mustafa Pasha was an experienced soldier and a successful commander; however, he also displayed avarice, pride, arrogance, and, above all, boundless ambition. He sought a military triumph that would eclipse the achievements of all his predecessors, including those of Sultan Suleiman the Magnificent.

Pretext for ambitious campaign

Meanwhile, the situation appeared far less favorable for the Ottoman Empire’s principal rival, the Habsburg Monarchy. Influenced by his Jesuit advisers, Emperor Leopold I pursued policies of religious persecution within his Hungarian domains. These measures provoked widespread discontent and ultimately led to a Hungarian uprising under the leadership of Emeric Thököly.

The Hungarian rebels, however, were fully aware that they could not successfully challenge the vast resources of the Habsburg Monarchy on their own. At the same time, they recognized that the Ottoman Empire offered a comparatively more tolerant environment for non-Muslim communities. The Ottoman system, grounded in Islamic law and longstanding administrative practice, generally afforded greater religious freedom than was available in many parts of contemporary Europe. Consequently, Thököly and his followers increasingly looked to the Ottomans as potential allies in their struggle against Habsburg rule.

This situation provided Kara Mustafa Pasha, who was eager to attain lasting glory, with an ideal opportunity to realize his ambitions. Yet a significant obstacle remained: a truce between the Ottoman and Habsburg Empires was still in force and was not due for renewal for another three years. Consequently, the Ottomans required a legitimate justification for embarking upon a new war against the Habsburgs.

In an effort to secure Sultan Mehmed IV’s approval for military action, Kara Mustafa Pasha allegedly produced forged reports from the frontier, claiming that Habsburg forces had violated the terms of the truce. These accusations helped create the political conditions necessary for advocating a renewed conflict with the Habsburg Monarchy.

Armed with these reports, Kara Mustafa Pasha succeeded in persuading Sultan Mehmed IV to declare war on the Habsburg Monarchy. News of the Ottoman preparations caused considerable alarm in Vienna, where the Habsburg government sought to avoid a renewed conflict at almost any cost. In an effort to preserve peace, the Habsburgs dispatched an embassy to Constantinople to negotiate with the Ottoman government.

As preparations for war advanced, Kara Mustafa Pasha sought a fatwa to legitimize the campaign. Significantly, the Grand Mufti initially refused to sanction the war and instead argued that the existing truce should be honored. Nevertheless, Kara Mustafa Pasha succeeded in overcoming this opposition and securing the political support necessary for military action. With the final obstacles removed, the die was cast: the Ottoman Empire would once again march onto the plains of Hungary.

Vienna as 'Red Apple'

The officially declared objective of the campaign was to capture the strategically important fortresses of Raab (in Győr) and Komarom. Kara Mustafa Pasha, however, harbored a far more ambitious goal, one that he concealed from Sultan Mehmed IV. He aspired to achieve what none of his predecessors had accomplished: the conquest of Vienna, the capital of the Habsburg Monarchy.

As one of Europe’s foremost political, religious and cultural centers, Vienna occupied a prominent place in both Ottoman and European perceptions. It had resisted even the armies of Sultan Suleiman the Magnificent during the siege of 1529, and therefore, it was often regarded as the next "Red Apple" (ultimate goal of conquest) in Ottoman political imagination.

Numerous legends further enhanced Vienna’s mystique. Among them was the belief that the treasures of the Sasanian ruler Khosrow I were hidden within the city. Other traditions portrayed Vienna as an impregnable fortress whose conquest was virtually impossible. In some contemporary and popular apocalyptic narratives, the eventual fall of the city was even associated with the coming of the end times. Whether grounded in reality or legend, such beliefs contributed to Vienna’s extraordinary prestige and made its capture an objective of immense symbolic value.

The Ottoman advance toward Vienna spread fear throughout Central Europe and caused widespread alarm among Christian populations. As the Ottoman army approached, many inhabitants fled the city, including Emperor Leopold I, who relocated his court to safety. At the same time, however, the emperor worked to secure support from the princes of the Holy Roman Empire and from King John III Sobieski of the Polish-Lithuanian Commonwealth.

The Habsburg strategy was straightforward: Vienna would hold out for as long as possible while a relief army was assembled and marched to its aid. If the defenders could withstand the siege, the arriving coalition forces would compel the Ottomans to abandon their operations.

Siege begins: Tactical hesitation

Under the command of Kara Mustafa Pasha, the Ottoman army formally laid siege on Vienna on July 14, 1683. During the course of the siege, several opportunities arose that might have enabled the Ottomans to capture the city more rapidly. Kara Mustafa Pasha, however, was reluctant to subject Vienna to a devastating bombardment. According to contemporary and later accounts, he hoped to take the city largely intact, thereby preserving both its wealth and its infrastructure. A less damaged Vienna, it was believed, would yield greater rewards than a city reduced to ruins by artillery fire.

This caution, while understandable from the perspective of maximizing the value of the conquest, prolonged the siege and has often been cited by historians as one of the factors that ultimately contributed to the Ottoman failure before Vienna.

The prolonged siege ultimately proved disastrous for the Ottoman army. The intense heat of the summer, combined with the hardships of trench warfare and continuous labor, severely weakened the besieging forces. Nevertheless, Vienna’s defenders were themselves nearing exhaustion, and by Sept. 11, 1683, the city stood on the brink of collapse. Had relief not arrived when it did, Vienna might well have fallen to the Ottomans.

Withdrawal of exhausted army

Unfortunately for the Ottomans, the relief army reached the city at the critical moment. On Sept. 12, 1683, the coalition forces under the command of King John III Sobieski launched their attack against the Ottoman positions. The Ottomans suddenly found themselves caught between the garrison of Vienna and the advancing relief army. Among the most celebrated episodes of the battle was the massive cavalry charge of the Polish Winged Hussars, which later became one of the most famous military actions in European history.

Kara Mustafa Pasha personally directed the defense of the Ottoman camp and attempted to rally his troops. Yet the situation was beyond recovery. After nearly two months of arduous campaigning and siege operations, the Ottoman army was exhausted, while the coalition forces entered the battle fresh and determined. Despite the deteriorating circumstances, Kara Mustafa Pasha reportedly resolved to continue the struggle rather than surrender.

According to contemporary accounts, some of his senior officers argued that his survival was essential to preventing the complete destruction of the Ottoman army. Accepting their advice, Kara Mustafa Pasha withdrew from the battlefield and retreated toward Belgrade with the remnants of his forces.

Cost of defeat: Execution

The consequences of the defeat proved fatal for Kara Mustafa Pasha. Proud and ambitious, he had accumulated numerous political enemies within the Ottoman capital, many of whom seized upon the failure before Vienna to make him the principal scapegoat for the disaster.

However, he also had many supporters, and for good reason. Even some individuals whom Kara Mustafa Pasha had previously condemned or opposed reportedly argued that he remained one of the few statesmen capable of steering the empire through the crisis that now confronted it.

Their appeals, however, went unheeded. Acting on the orders of Sultan Mehmed IV, Kara Mustafa Pasha was executed by strangulation in Belgrade in December 1683.

Whatever his shortcomings as a statesman and commander, Kara Mustafa Pasha had been one of the most capable figures of his generation. His death deprived the Ottoman government of an experienced leader at a moment when the empire faced one of the gravest challenges in its history. In the years that followed, the Ottomans struggled to replace the authority and administrative ability that he had embodied.

Turning of Ottoman tide

Thus ended the famous Second Siege of Vienna.

In the author's view, the siege represents one of the most significant turning points in Ottoman history. Most importantly, it marked the end of the empire's long era of territorial expansion into Central Europe and forced the Ottomans increasingly onto the defensive. Although historians debate the precise origins and nature of the so-called "Ottoman decline,” the failure before Vienna undeniably revealed vulnerabilities that had previously been less apparent.

The defeat also encouraged the formation of a broad anti-Ottoman coalition. Under the auspices of the Holy League, the Habsburg Monarchy, the Polish-Lithuanian Commonwealth, and the Republic of Venice joined forces against the Ottoman Empire. They were later joined by the Tsardom of Russia.

The conflict that followed, commonly known as the Great Turkish War, lasted from 1683 to 1699 and inflicted a series of severe defeats upon the Ottomans. It concluded with the Treaty of Karlowitz, under which the Ottoman Empire ceded extensive territories for the first time in its history through a major multilateral peace settlement. The treaty fundamentally altered the balance of power in Eastern and Central Europe and is often regarded as the beginning of a new phase in Ottoman-European relations.

For many Europeans, the battle came to represent the moment at which the Ottoman advance into Central Europe was finally halted. Although the Ottoman Empire remained a formidable military power for decades to come, the aura of invincibility that had surrounded Ottoman arms since the 16th century suffered a severe blow. European rulers and statesmen increasingly came to believe that the Ottomans could not only be resisted but also defeated.

The victory also fostered a new sense of cooperation among Christian powers. Political rivalries that had often divided European states were, at least temporarily, overshadowed by the perception of a common Ottoman threat. This spirit of cooperation eventually found expression in the Holy League, whose members continued the struggle against the Ottoman Empire for the next 16 years. The resulting conflict transformed the political landscape of Central and Southeastern Europe and contributed significantly to the rise of Habsburg power.