Ottoman–Habsburg wars

The Ottoman–Habsburg wars refers to the military conflicts between the Ottoman Empire and the Habsburg dynasties of the Austrian Empire, Habsburg Spain and in certain times, the Holy Roman Empire and the Kingdom of Hungary. The war would be dominated by land campaigns in Hungary and Croatia. Initially, Ottoman conquests in Europe made significant gains with a decisive victory at Mohács reducing around one third (central) part of Kingdom of Hungary to the status of an Ottoman tributary.

By the 16th century, the Ottomans had become a serious threat to Europe, with Ottoman Barbary ships sweeping away Venetian possessions in the Aegean and Ionia. The Protestant Reformation, the France–Habsburg rivalry and the numerous civil conflicts of the Holy Roman Empire served as distractions. Meanwhile the Ottomans had to contend with the Persian Safavid Empire and to a lesser extent the Mamluke Sultanate, which was defeated and fully incorporated into the empire.

Later, the Peace of Westphalia and the Spanish War of Succession in the 17th and 18th centuries respectively left the Austrian Empire as the sole firm possession of the House of Habsburg. By then, however, European advances in guns and military tactics outweighed the skill and resources of the Ottomans and their elite Janissaries, enabling the Habsburgs to retake Hungary. The Great Turkish War ended with three decisive Holy League victories at Vienna, Mohács and Zenta. The wars came to an end following Austria's disappointing performance in the war of 1787-1791, which Austria fought in alliance with Russia. Intermittent tension between the two countries continued throughout the nineteenth century, but they never again fought each other in a war, and ultimately found themselves allied in World War I, in the aftermath of which both empires were dissolved.

Origins
Main article in Byzantine–Ottoman wars and Ottoman–Hungarian Wars

The origins of the wars are clouded by the fact that although the Habsburgs were occasionally the Kings of Hungary and Emperors of the Holy Roman Empire (though almost always that of the Holy Roman Empire after the 15th century), the wars between the Hungarians and the Ottomans included other Dynasties as well. Naturally, the Ottoman Wars in Europe attracted support from the West, where the advancing and powerful Islamic state was seen as a threat to Christendom in Europe. The Crusades of Nicopolis and of Varna marked the most determined attempts by Europe to halt the Turkic advance into Central Europe and the Balkans.

For a while the Ottomans were too busy trying to put down Balkan rebels such as Vlad Dracula. However, the defeat of these and other rebellious vassal states opened up Central Europe to Ottoman invasion. The Kingdom of Hungary now bordered the Ottoman Empire and its vassals.

After King Louis II of Hungary was killed at the Battle of Mohács, his widow Queen Mary fled to her brother the Archduke of Austria, Ferdinand I. Ferdinand's claim to the throne of Hungary was further strengthened by the fact that he had married Anne, the sister of King Louis II and the only family member claimant to the throne of the shattered Kingdom. Consequently Ferdinand I was elected King of Bohemia and at the Diet of Pozsony he and his wife were elected King and Queen of Hungary. This clashed with the Turkish objective of placing the puppet John Szapolyai on the throne, thus setting the stage for a conflict between the two powers.

Habsburg advance
Ferdinand I attacked Hungary, a state severely weakened by civil conflict, in 1527, in an attempt to drive out John Szapolyai and enforce his authority there. John was unable to prevent Ferdinand's campaigning which saw the capture of Buda and several other key settlements along the Danube. Despite this, the Ottoman Sultan was slow to react and only came to the aid of his vassal when he launched a huge army of about 120,000 men on 10 May 1529.

Siege of Vienna
The Ottoman Sultan, Suleiman the Magnificent, easily wrestled from Ferdinand most of the gains he had achieved in the previous two years – to the disappointment of Ferdinand I, only the fortress of Bratislava resisted. Considering the size of Suleiman's army and the devastation wrought upon Hungary in the previous few years it is not surprising that the will to resist one of the world's most powerful states was lacking in many of the recently garrisoned Habsburg settlements.

The Sultan arrived at Vienna on 27 September the same year. Ferdinand's army was some 16,000 strong – he was outnumbered roughly 7 to 1 and the walls of Vienna were an invitation to Ottoman cannon (6 ft thick along some parts). Nonetheless, Ferdinand defended Vienna with great vigour. By October 12, after much mining and counter-mining an Ottoman war council was called and on October 14 the Ottomans abandoned the siege. The retreat of the Ottoman army was hampered by the resistance of Bratislava which once more bombarded the Ottomans. Early snowfall made matters worse and it would be another three years before Suleiman could campaign in Hungary.

Little War
After the defeat at Vienna, the Ottoman Sultan had to turn his attention to other parts of his impressive domain. Taking advantage of this absence, Archduke Ferdinand launched an offensive in 1530, recapturing Gran and other forts. An assault on Buda was only thwarted by the presence of Ottoman Turkish soldiers. Much like the previous Austrian offensive, the return of the Ottomans forced the Habsburgs in Austria to go on the defensive once more. In 1532 Suleiman sent a massive Ottoman army to take Vienna. However, the army took a different route to Koszeg. After a defence by a mere 700-strong Croatian force, the defenders accepted an "honorable" surrender of the fortress in return for their safety. After this, the Sultan withdrew content with his success and recognizing the limited Austrian gains in Hungary, whilst at the same time forcing Ferdinand to recognize John Szapolyai as King of Hungary.

Whilst the peace between the Austrians and the Ottomans would last for nine years, John Szapolyai and Ferdinand found it convenient to continue skirmishes along their respective borders. In 1537 Ferdinand broke the peace treaty by sending his ablest generals to a disastrous siege of Osijek which saw another Ottoman triumph. Even so, by the Treaty of Nagyvárad, Ferdinand was recognized as the heir of the Kingdom of Hungary. The death of John Szapolyai in 1540 saw Ferdinand's inheritance robbed; it was instead given to John's son John II Sigismund. Attempting to enforce the treaty, the Austrians advanced on Buda where they experienced another defeat by Suleiman; the elderly Austrian General Rogendorf proved to be incompetent. Suleiman then finished off the remaining Austrian troops and proceeded to de facto annex Hungary. By the time a peace treaty was enforced in 1551, Habsburg Hungary had been reduced to little more than border land. However, at Eger the Austrians achieved a stunning victory, thanks in part to the efforts of the civilians present.

After the seizure of Buda by the Turks in 1541, the West and North Hungary recognized a Habsburg as king ("Royal Hungary"), while the central and southern counties were occupied by the Sultan ("Ottoman Hungary") and the east became the Principality of Transylvania. The vast majority of the seventeen and nineteen thousands Ottoman soldiers in service in the Ottoman fortresses in the territory of Hungary were Orthodox and Muslim Balkan Slavs instead of ethnic Turkish people. Southern Slavs were also acting as akinjis and other light troops intended for pillaging in the territory of present-day Hungary.

The Little war saw wasted opportunities on both sides; Austrian attempts to increase their influence in Hungary were just as unsuccessful as the Ottoman drives to Vienna. Nonetheless, there were no illusions as to the status quo; the Ottoman Empire was still a very powerful and dangerous threat. Even so, the Austrians would go on the offensive again, their generals building a bloody reputation for so much loss of life. Costly battles like those fought at Buda and Osijek were to be avoided, but not absent in the upcoming conflicts. In any case Habsburg interests were split 3-way between fighting for a devastated European land under Islamic control, trying to stop the gradual decentralization of Imperial authority in Germany, and Spain's ambitions in North Africa, the Low Countries and against the French. Having said this, the Ottomans, whilst hanging on to their supreme power, could not expand upon it as much as they did in the days of Mehmet and Bayezid. Whilst the nadir of the Empire had yet to come, its stagnation would be characterized by the same campaigning that led to little real expansion. To the east lay further wars against their Shi'ite opponents, the Safavids.

Suleiman the Magnificent led one last final campaign in 1566, ending at the Siege of Szigetvar. The Siege was meant to be only a temporary stop before taking on Vienna. However, the fortress withstood against the Sultan's armies. Eventually the Sultan, already an old man at 72 years (ironically campaigning to restore his health), died. The Royal Physician was strangled to prevent news from reaching the troops and the unaware Ottomans took the fort, ending the campaign shortly afterward without making a move against Vienna.

1480–1540
Meanwhile, the Ottoman Empire rapidly began displacing her Christian opponents at Sea. In the 14th century, the Ottomans had only a small navy. By the 15th century, hundreds of ships were in the Ottoman arsenal taking on Constantinople and challenging the naval powers of the Italian Republics of Venice and Genoa. In 1480, the Ottomans unsuccessfully laid siege to Rhodes Island, the stronghold of the Knights of St. John. When the Ottomans returned in 1522, they were more successful and the Christian powers lost a crucial naval base.

In retaliation, Charles V led a massive Holy League of 60,000 soldiers against the Ottoman supported city of Tunis. After Hayreddin Barbarossa's fleet was defeated by a Genoan one, Charles put 30,000 of the city's residents to the sword. Afterwards, the Spanish placed a friendlier Muslim leader in power. The campaign was not an unmitigated success; many Holy League soldiers succumbed to dysentery, only natural for such a large overseas army. Furthermore, much of Barbarossa's fleet was not present in North Africa and the Ottomans won a victory against the Holy League in 1538 at the Battle of Preveza.

Siege of Malta
Despite the loss of Rhodes, Cyprus, an island further from Europe than Rhodes, remained Venetian. When the Knights of St. John moved to Malta, the Ottomans found that their victory at Rhodes only displaced the problem; Ottoman ships came under frequent attacks by the Knights, as they attempted to stop Ottoman expansion to the West. Not to be outdone, Ottoman ships struck many parts of southern Europe and around Italy, as part of their wider war with France against the Habsburgs (See Italian Wars). The situation finally came to a head when Suleiman, the victor at Rhodes in 1522 and at Djerba decided in 1565 to destroy the Knight's base at Malta. The presence of the Ottoman fleet so close to the Papacy alarmed the Spanish, who began assembling first a small expeditionary force (that arrived in time for the siege) and then a larger fleet to relieve the Island. The ultra-modern star shaped fort of St Elmo was taken only with heavy casualties; the rest of the island was too much. Even so, Barbary piracy continued and the victory at Malta had no effect on Ottoman military strength in the Mediterranean.

Cyprus & Lepanto
The death of Suleiman the Magnificent in 1566 brought Selim II to power. Known by some as "Selim the Sot", he assembled a massive expedition to take Cyprus from the Venetians, an Island far closer to Ottoman-controlled Middle East than to Venice. The other military option that Selim opted out of was to assist the Moorish rebellion that had been instigated by the Spanish crown to root out disloyal Moors. Had Suleiman succeeded in landing in the Iberian peninsula, he may have been cut off, for after he had captured Cyprus in 1571 he suffered a decisive naval defeat at Lepanto. The Holy League, assembled by the Pope to defend the Island arrived too late to save it (despite 11 months of resistance at Famagusta) but having collected so much of Europe's available military strength, sought to inflict a blow on the Ottomans, which with better supplied ammunition and armor, they did. The chance to retake Cyprus was wasted in the typical squabbling the followed the victory, so that when the Venetians signed a peace treaty with the Ottomans in 1573 they did so according to Ottoman terms.

Thirteen Years' War 1593–1606


After Suleiman' death in 1566, Selim II posed less of a threat to Europe. Though Cyprus was captured at long last, the Ottomans failed against the Habsburgs at sea (see above Battle of Lepanto). Selim died not too long after, leaving his son Murad III. A hedonist and a total womanizer, Murad spent more time at his Harem than at the war front. Under such deteriorating circumstances, the Empire found itself at war with the Austrians yet again. In the early stages of the war, the military situation for the Ottomans worsened as the Principalities of Wallachia, Moldova and Transylvania each had new rulers who renounced their vassalship to the Ottomans. At the Battle of Sisak, a group of ghazis sent to raid the insubordinate lands in Croatia were thoroughly defeated by tough Imperial troops fresh from savage fighting in the Low countries. In response to this defeat, the Grand Vizier launched a large army of 13,000 Janissaries plus numerous European levies against the Christians. When the Janissaries rebelled against the Vizier's demands for a winter campaign, the Ottomans had captured little other than Veszprém.

1594 saw a more fruitful Ottoman response. An even larger army was assembled by the Grand Vizier Sinan Pasha. In the face of this threat, the Austrians abandoned a siege of Gran, a fortress that had fallen in Suleiman's career and then lost Raab. For the Austrians, their only comfort in the year came when the fortress of Komárno held out long enough against the Vizier's forces to retreat for the winter.



Despite the previous years' success, situation for the Ottomans worsened yet again in 1595. A Christian coalition of the former vassal states along with Austrian troops recaptured Gran and marched southward down the Danube. Michael the Brave, the prince of Wallachia started a campaign against the Turks (1594–1595), conquering several castles near the Lower Danube, including Giurgiu, Brăila, Hârşova, and Silistra, while his Moldavian allies defeated the Turks in Iaşi and other parts of Moldavia. Michael continued his attacks deep within the Ottoman Empire, taking the forts of Nicopolis, Ribnic, and Chilia and even reaching as far as Adrianople. At one point his forces reached Edirne, the former Ottoman capital city; no Christian army had set foot in the region since the days of the Byzantine Empire under the Palaiologoi. Following the defeat of the Ottoman army in Wallachia (see the Battle of Călugăreni) and the series of unsuccessful confrontations with the Habsburgs (culminating in the devastating siege and fall of Ottoman-held Esztergom), alarmed by the success and proximity of the threat, the new Sultan Mehmed III strangled his 19 brothers to seize power and personally marched his army to the north west of Hungary to counter his enemies' moves. In 1596 Eger fell to the Ottomans. At the decisive Battle of Keresztes, a slow Austrian response was wiped out by the Ottomans. Mehmet III's inexperience in ruling showed when he failed to reward the Janissaries for their efforts in battle; rather he punished them for not fighting well enough and thereby incited a rebellion.

Keresztes was a bloodbath for the Christian armies – thus it is surprising to note that the Austrians renewed the war against their enemies in the summer of 1597 with a drive southward, taking Pápa, Tata, Raab (Győr) and Veszprém. Further Habsburg victories were achieved when a Turkish relief force was defeated at Grosswardein (Nagyvárad). Enraged by these defeats, the Turks replied with a more energetic response so that by 1605, after much wasted Austrian relief efforts and failed sieges on both sides, only Raab remained in the hands of the Austrians. In that year a pro-Turkish vassal prince was elected leader of Transylvania by the Hungarian nobles and the war came to a conclusion with the Peace of Zsitva-Torok.

Conquest of Crete
The Knights of Malta, emboldened by declining Turkish offensive power, began attacking Turkish ships in the Mediterranean. The Turks retaliated by besieging Candia on Crete in 1648. The Venetians were left to defend their last major Aegean island alone, as Austria was still recovering from the devastation of the Thirty Years' War and Spain remained defiant against the French.

Since the darker days for Venice of the 16th century, the Venetian fleet was a more potent force, defeating the Turks in their attempts to take the Island. So long as the Venetians had naval supremacy, the Ottomans could do little on land at Crete, and the blockade established by Venice at the Dardanelles was more than a serious humiliation. Within 10 years the Spanish had signed a peace treaty with the French in 1659 and war with Austria resumed in the later 1660s. With the war going slow and the Austrians, Spanish and Venetians operating with the initiative, the Grand Vizier seized power in the name of the Sultan and conducted a far more rigorous effort. Though beaten by the Austrians, the Ottomans concluded a favorable peace in 1664 and the Venetians were finally defeated at sea, ending the embarrassing blockade at the Dardanelles, so close to the Ottoman Capital. The Island fell after many years of siege, thanks to the skillful resources of the Grand Vizier, his organization of an army misused for many years and the French attacks on Austria, which forced her to postpone any offensives into Hungary.

Great Turkish War
In 1663, the Ottomans launched a disastrous invasion of Austria, ending at the Battle of St Gotthard. The battle was won by the Christians, chiefly through the attack of 6,000 French troops led by La Feuillade and Coligny. The Austrians were unable to follow up on this victory due to the intervention of French forces in the Rhine; in such circumstances the Protestant allies of the Catholic Habsburgs would have proven unreliable, wanting instead to have the Austrians and themselves fight the French in a German coalition. The Ottomans therefore turned their attention north again against the Polish–Lithuanian Commonwealth. By now, the Kingdom had fallen into a terrible state; the Sejm had divided loyalties and the treasury was bankrupt. It is therefore noteworthy that Jan III Sobieski of the Poles led a decisive victory against the Ottomans at the Second battle of Khotyn.

Restless, the Ottomans were to have another chance in 1682, when the Grand Vizier marched a massive army into Hungary and to Vienna in response to Habsburg raids into Ottoman controlled Hungary.

Siege of Vienna
In 1683, after 15 months of mobilizing forces, the Grand Vizier reached Vienna to find the city well defended and prepared. Worst of all for the Vizier were the numerous alliances established by the Austrians, including one with Jan Sobieski. When the siege of Vienna began in 1683, the Polish King and his coalition of Germans and Poles arrived just as the city's defense became untenable. In a decisive battle, the Ottomans were defeated and the siege lifted.

Holy League Counter
In 1686, two years after the unsuccessful siege of Buda, a renewed European campaign was started to enter the erstwhile capital of medieval Hungary. This time, the Holy League's army was twice as large, containing over 74,000 men, including German, Croat, Dutch, Hungarian, English, Spanish, Czech, Italian, French, Burgundian, Danish and Swedish soldiers, along with other Europeans as volunteers, artilleryman, and officers, the Christian forces reconquered Buda. (See: Siege of Buda)

In 1687, the Ottomans repaired their armies and marched north once more. However, Duke Charles intercepted the Turks at the Second Battle of Mohács and avenged the loss inflicted on the last Hungarian King over 160 years ago by Suleiman the Magnificent. Pressing southward, the Ottomans continued to resist the Austrians, denying them an opportunity to negotiate from a position of strength. Only when the Ottomans suffered yet another disastrous battle at the crossing at Zenta in 1697 did the Ottomans sue for peace; the resulting treaty of Karlowitz in 1699 secured vast amounts of Central Europe, mostly Hungary, for the Austrians. Throughout Europe, both Protestants and Catholics hailed Prince Eugene of Savoy as "the savior of Christendom" – English volunteers, including a son of Prince Rupert (nephew of Charles I of England) and Protestants from as far as Scotland fought in the Prince's army. For the Ottomans, the years between 1683 and 1702 were a sad time; 12 Grand Viziers were deposed in 19 years – the legacy of what was at one time under Köprülü Mehmed Pasha the most powerful position of one of the most powerful Empires in the world.

18th Century wars
Although the Great Turkish War was a disaster for the Ottomans, from which they were unable to recover, the Habsburgs were soon drawn into another destructive European War against the French, their traditional rivals. The King of Spain was childless and approaching death. The two most powerful claimants to the Spanish throne were the Austrian branch of the Habsburgs and the French Bourbon dynasty (the latter being the closest claimant). The Protestant powers of England (later Great Britain after 1707) and the Netherlands were concerned with the consequences of either Catholic power seizing all the lands. When the Bourbons decided to inherit the entire Empire without partitioning it with the Austrians, war broke out lasting until 1714. By the time the war had ended, Eugene's reputation in battle had risen further with victories such as those at Blenheim. Nonetheless, the Bourbons had succeeded in de facto annexing Spain to their territories by placing a member of the Bourbon lineage on the Spanish throne. Even so, the Italian provinces of the Spanish crown passed to the Austrians, and the Catholic portions of the Low countries – rather than passing to the Dutch who coveted them, or to the French who desired them as part of their expansion of their borders, returned to Imperial control once more.

With the war over, Eugene turned his attention south again. Another victory was added to his record in 1716 at the battle of Petrovaradin, a stunning victory in which the cunning Prince saved his army from defeat at the hands of larger force and disease. However, Austria failed to produce a military commander worthy enough to succeed him. In the absence of such a talented leader, the Ottomans won a surprising victory against their Christian opponents at the Battle of Grocka in 1739. Drunken, outnumbered and in a disorderly fashion, the Ottomans had forced the overconfident Austrians to surrender.

The Austrians defeated the Ottomans decisively in the Austro–Turkish War (1787–1791), but their territorial gains were meager in the Treaty of Sistova.

19th Century
For the next 100 years, the Austrians and the Ottomans both began to slowly lose their power to the French, British, Prussians and Russians. The key problem faced by both Empires was the rise of the new industrial era. New industries in Germany, France and Britain produced massive quantities of manufactured goods that aided in war and diplomacy. Both the British and the French had colonial empires that fueled their economies with raw materials, whilst the Germans found what they needed in the Ruhr valley. Although the Russians had no such colonial empire, they did have vast amounts of territory and manpower. Both the Ottomans and the Austrians lacked the heavy industry of their other European counterparts, but the Ottomans were further behind than the Austrians. Thus, Ottoman power decayed faster than Austrian power. In the Balkans, the increasingly prevalent nationalistic cries for independence became a bigger problem for the more militarily incompetent Ottomans. After 1867, the Austrians compromised with the Hungarians to form Austro-Hungary, thus preventing a major ethnic group from rebelling in the shorter term. The same benefits could not be had with the Ottomans. Efforts to catch up with European technology led officers and intellectuals to study abroad—a plan that backfired for the Ottomans when these individuals brought back European ideas of Enlightenment and egalitarianism. These ideas subsequently clashed with the traditional Turkish-dominated, autocratic, millet system of the Ottomans. Therefore, Ottoman power collapsed more rapidly than Austrian power, and they were powerless to stop Bosnia from being occupied in 1878 (officially annexed in 1908). Had it not been for the Western powers of Britain, France and Prussia, the Ottomans would have faced more defeats against the Austrians and their newer enemies, the Russians.

World War I
Relations between Austria and the Ottomans began to improve when they saw a common threat in Russia and a common ally in Germany in countering the threat of the Tsar. The Ottomans had hoped the Germans would industrialize their nation to defend itself against the Russians, who had taken the "anti-Turk crusade" to a more committed level, driving the Turks out of the Crimea and Caucasus. Meanwhile the German Empire of Prussia appealed to the Austrians through a common culture, language and the lenient terms imposed after the Austro–Prussian War. The Austrians were in no hurry to see Russia advance at the cost of the Ottomans towards their borders. Thus, in the years before World War 1, the two former enemies found themselves allies against the French, the Russians and the British. In 1918, the Austro-Hungarian Empire surrendered to partition under the Treaty of Saint-Germain, as did the Ottomans under the Treaty of Sèvres.