Siege of Vienna (1529)

Siege of Vienna
Part of the Ottoman wars in Europe
Engraving of clashes between the Austrians and Ottomans outside Vienna, 1529
Date September-October 14, 1529 Location Vienna, Austria Result Decisive Christian victory
Belligerents
Austria with Bohemian, German & Spanish mercenaries	Ottoman Empire
Commanders and leaders
Nicholas, Graf von Salm	Suleiman I
Strength
26,700 and 72 guns	120,000 (108,000 ottoman infantry and cavalry, 12,000 janissaries) and 300 guns
Casualties and losses
Unknown	20,000-25,000

The Siege of Vienna of 1529, as distinct from the Battle of Vienna in 1683, was the Ottoman Empire's first attempt to capture the city of Vienna located in modern day Austria. Traditionally the event has held special significance in Western history, indicating The Ottoman Empire's highwater mark and signalling the end of Ottoman expanision in central Europe, although a century of tension and incursions would follow, culminating in the Battle of Vienna in 1683.

Background

With the defeat of the Kingdom of Hungary at the Battle of Mohács In August 1526, Sultan Suleiman I (also known as Suleiman the Lawgiver or Suleiman the Magnificent) facillitated the collapse of Hungarian rule causing the country to fragment into a number of small sucessor states. With Ottoman dominance in the eastern part of the country assured, western Hungary was quick to align itself with its large neighbour Austria, whose ruler, Ferdinand I of Habsburg, claimed the Hungarian throne through the sucession of his wife .

With the carving up of the country between two powerful states, ineveitably hositilities were quick to flare up. Concerned about the threat of having such a large and potentially powerful enemy on his border, Suleiman decided to mount a military expedition to remove the Austrian threat. In the spring of 1529, three years after the defeat of Hungary, Suleiman's armies mustered in Ottoman Bulgaria, with Suleiman acting as the commander-in-chief, and his grand vizier, a former Greek slave called Ibrahim Pasha, acting as serasker (a commander equivalent to a Western field marshal).

The exact numbers of the Ottoman force are unknown and contiune to be the source of much conjecture amongst military historians. It is agreed that the Sultan's large army included a sizable force of the elite janissary corps and a small number of Christian Hungarians fighting for their new Turkish ruler. The army was also well provisioned for seige warfare and took at least 300 cannons and seige guns with it.

The March to Vienna

The spring rains characteristic of south-eastern Europe were particularly heavy that year, causing flooding in Bulgaria, and making many of the major roads on Suleiman's route barely passable. The weather resulted in the loss of many of the Ottoman camel, and many of the large calibre guns became hoplessly mired and had to be left behind. Acting against the advice of serasker Ibrahim Pasha, however, Suleiman pressed on, saying: "It is beneath my dignity to allow the weather to interfere with my plans".

The news of the Ottoman advance caused panic within Vienna, many of the inhabiatants remembering the fate of the German defenders of Pest, who were massacred by the Sultans Janissaries after their surrender. Ferdinand I withdrew to the relative safety of Habsburg in Bohemia following the failure of pleas to his brother, Emperor Charles V, for help. This left the city inhabitants no choice except from preparing for a long seige, and Operational command of the defence was duly given to a seventy-year-old German mercenary named Nicholas, Graf von Salm.

Salm arrived at the head of a relief force which included German Landsknechte mercenary pikemen, and Spanish musketmen. Taking charge of the garrison, Salm began work on modernising and reinforcing the city's three-hundred-year-old walls, pierced by four gates and surrounding St. Stephen's Cathedral, which he made his headquarters. To make sure that the city could withstand a lenghty seige, he oversaw the digging of fireproof magazines, erected earthen bastions, and reinforced the city walls. Flammable shingles were torn from the roofs, and the four gateways were also heavily reinforced.

In order preserve what food the city had stored in the event of siege, the Austrians were forced to expell 4,000 women, children, and elderly men out of the city in an escorted column. Unfortunately the column was intercepted by Ottoman forces and attacked at Traismauer. The Austrians later reported that some of the victims were impaled on stakes, whilst some young women were sold as slaves.

Opening

The Ottoman army that arrived in late September, two months behind schedule, had been badly mauled by the long march into Austrian territory. The heavy rains and miserable conditions had caused further reductions to the Sultan's strength, leaving him with very few camels and heavy equipment. Many of the troops arrived in Vienna in a poor state of health after the privations of the long march, and of those able to fight, a third were light cavalry (sipahis), who were ill prepared for siege warfare. On the next day the Ottoman's sent emissaries to negotiate the city's surrender, Salm, however, sent them away with honor but without reply.

On the following day, the remnants of the Ottoman artillery began to bombard the cities walls. However the lack of the larger caliber weapons meant that the remaining 300 cannon where too small to significantly damage the Austrian defensive earthworks. The Ottoman archers fared little better, causing a mild annoyance to the sheltering garrison, indeed it is reported that as balls crashed into the roof of St. Stephen's, Salm calmly remarked: "These pebbles are like the little pills my medico bids me swallow."

In an attempt to silence the Ottoman artillery, a small unit of a hundred cavalry under Eck von Reischach launched a small raid that took the Turks by surprise; killing two gun crews before being forced to retreat back to safety. Whilst this event arguably boosted Austrian morale, it had little effect on the Ottoman artillerymen who continued their bombardment unabated for several more days.

The Moles

Intelligence reached the defenders that the real purpose of the bombardment was to mask tunnelling efforts beneath the city. The Carinthian Gate, one of the city's four entrances, was the apparent target of this new assault, the intent being to blow up the towers and then attack with assault troops. Salm, an expert in tunnelling, quickly took ingenious steps against the efforts, including placing buckets of water and dried peas on drums near the cellar walls of homes adjacent to the gate: when they shook, an alarm was sounded and counter-miners would commence digging "like moles". What they discovered were six different tunnels advancing through the earth towards the helpless bastions.

The Austrians dug until they struck the enemy tunnels, some of which they found deserted but with powder kegs ready to be lit, and some which were still occupied by miners and immediately became the site of unconventional combat. Guns were unusable due to the proximity of the kegs, so the men fought hand-to-hand with whatever weapons or tools they could muster, many dying, in the words of one witness, like "devils from the nether pit of hell". As the battle continued and the fighting below ground grew even more fierce, new weapons were devised for the underground war, including Turkish cavalry maces and Austrian sharpened spades. At one point, a powderkeg exploded prematurely, killing dozens on both sides. The total death toll from the underground fighting is unclear, but it gave rise to the term that would come to define the battle: the Siege of the Moles.

The majority of the mines had been discovered before any damage could be done, but constant digging exhausted Viennese capabilities and on 5 October two mines exploded beneath the Salt Gate, leaving room enough for a company of soldiers to break through. Janissaries immediately stormed the breach but were met by twelve-foot pikes and halberds, repulsing them with heavy losses. Within hours the breaches were refilled.

The next night, the Austrians replied with a new form of deadly assault. Dozens or possibly hundreds of men wearing black cloaks and armed with homemade bombs, possibly one of the first appearances of the Molotov cocktail, exited the city in silence and strode into the Ottoman camps, tossing their bombs into tents before making their escape. As many as 2,000 Turks died unaware, while sleeping.

The fighting continued unabated. Some days later a mine finally exploded under the two towers of the Carinthian Gate, bringing them down and opening it to assault; but the advance was held back by Spanish harquebusiers, German pikemen and Bohemian two-handed swordsmen who killed 1200 Janissaries before the Janissaries retreated from the breach.

Endgame

As the mining went on day after day with no end in sight, Suleiman realised that the strategy might have become counter-productive. On October 11 more rain fell and thousands more camels died, while the Viennese began mounting cannons on rooftops, including the so-called "royals", with a greater range than any Turkish gun, that raked the Ottoman camps with nonstop fire. Also, the Turks had so devastated the surrounding land that food had begun to grow scarce. Suleiman held a council of war that decided upon a final assault.

On October 14, the attack began, with serasker Ibrahim leading the charge personally. The assualts were aimed at the ruined Carinthian Gate and the bastion at the citadel or burg. The attack was led by bashi-bazouks, militia intending to overwhelm the Austrians with sheer numbers, followed by the janissaries, who for the first time were offered the incentive of a bounty of silver. Suleiman ordered that regardless of losses the attack be launched three times: he would either win or suffer dearly in the attempt.

After one mine had been exploded and another had failed, the Turks broke through the breaches with screaming battle cries, only to be faced again with palisades and long pikes. The bashi-bazouks charged twice and fell back twice as they were cut down repeatedly by pike and musket. Next came the Ottoman janissaries struck with murderous fervor who were also beaten back under a hail of grenades and grapeshot fired from the cannons sited within the Burg, leaving behind piles of thier dead and wounded. Fearing Austrian collapse, Salm descended from St. Stephen's to assume personal command of the battle, he was hit almost immediately and fatally wounded.

Finally, without being ordered, the janissaries fell back, despite Ibrahim's efforts to whip them into another charge. They swarmed back to the camps, unpursued, and struck their tents. The siege was over.

Aftermath

The Turks quickly packed their campsites that night. Pandemonium reigned throughout, however, and many Austrian captives managed to escape to the walls of the city, where ladders were lowered for them, the Viennese still not believing it was all over. The defenders emerged the next day, to find no trace of the Ottoman army, and snow decending on thier adandoned camp.

Ottoman casualties were thought to have numbered about 20,000 to 25,000 men , many more than the garrison's; Austrian civilian casualties were doubtless greater, however, as most of the country south of Vienna had been depopulated.

In Vienna, the defenders examined each man allowed into the city after the siege for circumcision (a practice of the Jewish and Muslim faiths), believing the Turks had smuggled in spies, and promptly hanged those who failed the test.

Some historians speculate that Suleiman's aim in that final assault wasn't so much to take the city, as he knew winter was approaching, but to cause as much damage as possible, weakening it for a later attack. That second assault came in 1532, but it was held up too long in reducing the western Hungarian fort of Kőszeg, by which time winter was close and Charles V assembling 80,000 troops at Vienna. So instead of the planned siege, the invading troops retreated through and laid waste to Styria.

The invasion and subsequent siege exacted a ghastly price from both sides, with tens of thousands of soldiers and civilians dead and thousands more sold into slavery. It marked the end of the Ottoman advance towards the centre of Europe and the beginning of their long decline from being the dominant power of the Renaissance world. While they would remain strong for many years, eventually mounting another siege in 1683 before the Battle of Vienna, they would never again reach the same level of threat as in 1529.

Ferdinand I set up a funeral monument for Nicholas, Graf von Salm, to express his gratitude for the defender of Vienna. This Renaissance sarcophagus is now on display in the baptistry of the Votivkirche in Vienna.