On August 29, 1526, the Battle of Mohács took place in Hungary, where the Hungarian army suffered a crushing defeat at the hands of the Ottomans.

The dead Hungarian soldiers exceeded 24.000, including their king Ludwig II.
After the Battle of Mohács, Hungary was divided into three parts: "Royal" Hungary, under the rule of the Holy Roman Empire of the Habsburgs, the central part occupied by the Turks, and the autonomous but vassal Transylvania.
A series of Ottoman wars against the Habsburgs followed, culminating in the two sieges of Vienna.
During its first siege, when the Ottoman army had reached the borders of Austria in September 1529, cholera broke out in the Turkish camp, while the Austrians were also helped by the adverse weather conditions with heavy rainfall that made the siege difficult.
Thus, the walls of Vienna were fortified and the Turks' attempts to capture it failed. The siege ended in mid-October of the same year.

On August 15, 1664, a twenty-year peace agreement was concluded between Austria and Turkey.
In 1682, when the Turks' intentions to not renew the twenty-year agreement became apparent, Emperor Leopold I took care of and created alliances with Bavaria, Poland, and Saxony.
The Turkish forces, which attempted the second siege of Vienna, were under the leadership of Grand Vizier Kara Mustafa, who had approximately 200.000 men, while the Austrian forces numbered approximately 30.000.
In early July 1683, with the city's defenses already ready to collapse, Leopold abandoned Vienna and fled to the Danube city of Linz.
The defense of the city was left to 11.000 soldiers, who were reinforced by militia and volunteers. By early September, the Turks were digging trenches and blowing up the city walls and had occupied eastern parts of Vienna, with the Austrian army having retreated west of the Danube. The strength of the Austrian defenders of the city was reduced to 4.000 men, and the fate of Vienna now hung in the balance.
However, at the last minute, the allied forces of the Austrians arrived, to which other German principalities had been added under the care of the Pope.
On September 12, the decisive battle of Mount Kahlenberg took place. The decisive factor in this battle, which tipped the scales in favor of the Austrian allies, was the contribution of the Poles with 14.000 armored cavalry, 7.000 infantry and 28 cannons under King Jan III Sobieski.
The Turks found themselves between the city walls and the united allied forces under Sobieski and suffered a heavy defeat, after which the Ottoman Empire essentially began to shrink.
Already in the spring of 1684, through the mediation of the Pope, an alliance, known as the "Holy Alliance", was concluded between Leopold I and Poland-Lithuania and Venice. In 1686, Russia also joined the alliance.
In the following years, the Austrians went from defenders to attackers and gradually succeeded in conquering all of Hungary, creating the conditions for the formation of an ambitious expansionist policy of Austria with its eyes fixed on the Balkans for over 200 years.
In 1688, after the Austrians had taken Buda, Leopold I's advisors decided that peace should be made with the Turks to avoid a two-front struggle, in the west with the French and in the east with the Turks.

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