The Siege of Vienna, 1683

On September 12th, 1683 the armies of the Ottoman Empire were defeated in battle before the walls of Vienna. After 1529, this was the second and last time the Ottomans, the greatest Islamic empire in recent memory, would lay siege to Vienna and seriously threaten Europe.

Over the past few years, the Ottomans had already begun to experience a revival. Starting 1656 the leadership of the Ottoman state had fallen into the hands of the new grandee dynasty of Koprulu, an Albanian family of previously little importance. Beginning with the patriarch Koprulu Mehmed the family led a reversal of Ottoman fortunes across the board.

The Ottoman revival did not become a cause for concern until the next round of the Ottoman-Polish Wars. In this conflict, the Polish-Lithuanian Commonwealth lost control of a substantial chunk of its territory in the south. The lost territory included the Right Bank Cossack Hetmanate in 1672 and all to the forces of Grand Vizier Fazil Ahmed Pasha. While the war eventually ended in 1676 on far less severe terms the sudden resurgence of the Ottoman military strength was worrisome.

The same year the war against the Commonwealth ended saw the ascension of the third Koprulu Grand Vizier, Merzifonlu Kara Mustafa. Ambitious and talented Kara Mustafa intended to build on his adopted family’s accomplishments. From the beginning, the new administration was plunged into war. This war, against the Tsardom of Russia, ended in 1681 in the Ottomans’ favor and allowed them to turn to Europe.

There the Ottomans were faced by their most enduring foe, the Catholic Habsburg dynasty, and the Holy Roman Empire. Internally, the empire was experiencing the Counter-Reformation. The emperor, Leopold I, seemed to have two great goals in life. First, the end of the Protestants, and second the containment of Louis XIV, the Sun King of France.

Thus, it was the Habsburgs found themselves fighting a losing war with the Calvinist Hungarian leader Imre Thokoly, Prince of Transylvania. The success of the anti-Catholic cause attracted Ottoman attention, especially when Thokoly wrestled a large part of Northern Hungary from the Habsburgs. In 1682, the Grand Vizier negotiated to make Thokoly an Ottoman vassal as King of Central Hungary. Louis XIV saw the inevitable result of Kara Mustafa’s policy and sent word to his embassy in Constantinople to let the Ottomans know he did not plan to interfere.

With the French King’s promise, the Grand Vizier felt confident enough to begin to convince the sultan, Mehmed IV, to declare war. However, the sultan needed more convincing, and Kara Mustafa went as far as to falsify documents and manipulate the Habsburg desire for peace at all costs, to his advantage. On August 26th, Mehmed IV finally agreed to war and sent a message to Vienna telling the emperor to stay where he was until the sultan could arrive to take his head personally. Mehmed also let Leopold know his intent to wipe the population out in its entirety unless they converted to Islam.

The Ottoman army converged on Edirne, but with the lateness of the season did not leave. They had gathered there to await the Sultan’s blessing as supreme leader of Islam, and the invasion was pushed back to the following year.

The Christians took this time to recover from the shock of the Ottoman declaration of war and prepare. Leopold called on the Pope, Innocent XI, to help out with the diplomatic offensive. The Pope responded wholeheartedly but found his efforts to unite Christendom blocked by Louis XIV, who believed that an Ottoman victory would ensure France’s supremacy over Europe. The main battleground of the diplomatic war was the Sejm (Parliament) of the Polish-Lithuanian Commonwealth.

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King Jan III of the Poland-Lithuanian Commonwealth. Attributed to Jan Tricius [Public domain], via Wikimedia Commons.

The King of the Commonwealth, Jan III Sobieski, was more than willing personally to ride to war. But the law of the Commonwealth dictated the unanimous approval of the Sejm was needed first. As a result, France and Papacy competed for votes through 1682 and 1683. Frustration mounted as the situation continued over several sessions.

Meanwhile, the Ottoman war machine rumbled forward. On March 30th, 1683 the Ottoman Army left Edirne and marched north into Hungary. By May 3rd, they had reached Belgrade and were joined by the vassal armies of Imre Thokoly and the Chinggisid Khan of the Crimean Tatars. At a war council in Belgrade, the Grand Vizier decided on a change of plans. Rather then advance and besiege the Habsburg fortress at Gyor he opted to proceed directly to the capital at Vienna. The sultan had no objections and gave the go-ahead to the plan though he stayed behind in Belgrade. On July 7th, Ottoman plans became apparent to the Habsburg court and the emperor, with his nobles, most his army, and some 60,000 civilians abandoned Vienna. Only a skeleton garrison of 11,000 under Ernst Rudiger, Graf von Starhemberg, and 5,000 civilians remained when the Ottoman army finally arrived on July 14th. Their army totaled 120,000 men, with an extensive siege train.

On arrival, the Grand Vizier set up one of the most splendid siege camps in history and ordered his men to begin to set up siege trenches and bring up the artillery. Before the firing began Kara Mustafa sent forth an emissary to the walls, telling the garrison that if they laid down their arms and became Muslims they and the population would be spared. A resounding roar of defiance answered him, and the siege began.

The Ottoman siege would be the key element to sway the Sejm. With reports from Hungary and Austria coming in and one last massive bribe from Rome, the Sejm gave the unanimous decision to declare war on the Ottoman Empire. King Jan was already resolved to go to war regardless from the previous winter. Now with official sanction the King of the Commonwealth moved his forces ever closer to the western border.

On August 15th, he crossed into the Holy Roman Empire.  Toward the end of the month the Commonwealth army, composed of the finest forces he had to offer, met an Imperial army commanded by Leopold’s brother-in-law, Karl V of Lorraine. A combination of Austrian, Bavarian, Swabian, Franconian, and Protestant Saxon troops the ragtag forces had been steadily harassing the Ottomans for some time. With the arrival of the Commonwealth forces, the Christian leadership felt that they could now relieve Vienna. The allied troops numbered 87,000 in total. Of those 50,000 were Austrian and German, the remaining 37,000 being Commonwealth.

Meanwhile, the siege was not going well for the defenders. Merzifonlu Kara Mustafa Pasha was not an inpatient or hotheaded man and as far as he knew he had all the time in the world to conduct the siege. His actions were methodical and steady. When the Ottoman cannons, 300 in all, proved to be too light to breach Vienna’s walls he adopted tunneling instead. But Vienna’s walls were quite advanced, so undermining them was slow going. Ottoman tunnels were met by answering tunnels from Vienna, planting and defusing bombs back and forth steadily.

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Grand Vizier Kara Mustafa Pasha of the Ottoman Empire. See page for author [Public domain], via Wikimedia Commons.

But the Ottomans knew they were winning. On September 8th, the Ottoman sapper corps blew a massive chunk out of Vienna’s walls when they destroyed the Burg ravelin and the nearby Nieder wall. As the Ottoman infantry stormed the fortifications the defenders, now whittled down to 4,000 continued to hold grimly despite the damage. They were prepared to fight the Ottomans in the streets if needed.

However, help was coming. Two days earlier the allied forces had crossed the Danube at Tulln and were marching with all speed to Vienna, working out a solid command structure along the way. News of the breach caused them to move even faster. The King soon led the combined armies through the dense and mountainous forest region of the Wienerwald. On September 11th, Christian forces arrived on a small hill overlooking Vienna known as Kahlenberg and drove off an Ottoman observation force. They then lit up three large torches to let the Ottomans and the defenders know of their arrival.

The Ottoman response was lackluster. Kara Mustafa was convinced the natural terrain of the Wienerwald would prevent any force significant enough to threaten him from coming through. Fatally he had also underestimated the Christian resolve to defeat him. Even as his staff urged the Grand Vizier to break camp and wheel about to face the allied forces he refused. Instead, he moved a small force of 30,000 infantry and cavalry to his rear supported by cannons and the Crimean cavalry. At the same time he shifted most of his troops for one final attack on Vienna the next day on September 12th.

Meanwhile in the Christian camp the allied forces were preparing for battle. Jan III was careful in his deployment, putting the Austrians on the left flank, most of the German troops in the center, and the Commonwealth forces augmented by German infantry on the right.

In the early morning dawn of the next day, the Catholic forces held Mass while the Protestants held their service, both prayed for victory. At 5:30 AM, the Ottomans, moved to dislodge them, except for the Crimean cavalry. In a fit of anger at the prior treatment, the Tartars had chosen to peel off and raid the suburbs of Vienna, abandoning their positions.

Duke Karl reacted quickly and led his troops forward, joined by the Imperial infantry in the center. The resulting battle would soon dissolve into a steady concerted effort to push back the Ottoman line. However, it was slow going as the heavy woods made the fighting and advance difficult on both sides. The whirling battle soon began to drag more Ottoman troops into the fray.  But, Kara Mustafa kept his best troops, the crack Janissaries, and the heavy cavalry out of the fighting and in the trenches before Vienna.

Even as the Christians tried to break the siege the Ottomans were attempting to create a second large hole in the walls, making the relief effort and the defense futile. But the defenders, already suspicious of another mining attempt like that of September 8th, discovered a massive bomb under the Lobel bastion just in time. The last ditch chance for victory had effectively gone up in smoke in the early afternoon around 1:00.

At the same time, the bomb was diffused the Commonwealth forces had finally managed to make their way onto the battlefield proper and took a position on the ridge. King Jan then detached his infantry to aid the Imperial center in turning the Ottoman lines. The Commonwealth cavalry then returned to the woods with a unit of Imperial cavalry.

At 2:30 PM the Christian cavalry, led by Poland’s winged hussars, burst from their cover on the far right of the Ottoman lines. The impact of such a charge head-on nearly broke the stressed siege lines on contact. Within another 3 hours, the rest of the besiegers broke and fled as well under pressure from the Austrian left. The last force to resist was the 20,000 man Janissary corps, but even they were overrun under the press of the Christian advance and fled.

The Grand Vizier then ordered the withdrawal to Belgrade, which turned into a rout. Leaving their whole camp and its riches behind, which greatly benefited the victors. Jan III was the first to reach the Grand Vizier’s tent from which he received the delirious and joyful cheers of his army and the defenders of Vienna as the savior of Europe. The city was saved.

As the allied troops plundered the camps, Jan III took the time to dictate a letter to the Pope by which he would report his victory to all Europe. In this letter, he made his famous paraphrase of Julius Caesar’s dispatch from the battle of Zela in 47 BC:

“Venimus, Vidimus, Deus Vicit” We Came, We Saw, God Conquered.