Ottoman–Habsburg wars: The siege of Vienna ended with Austrian forces repelling the invading Turks, turning the tide against almost a century of conquest in Europe by the Ottoman Empire.

The Ottoman–Habsburg wars were fought from the 16th to the 18th centuries between the Ottoman Empire and the Habsburg monarchy, which was at times supported by the Kingdom of Hungary, Polish–Lithuanian Commonwealth, The Holy Roman Empire, and Habsburg Spain. The wars were dominated by land campaigns in Hungary, including Transylvania and Vojvodina, Croatia, and central Serbia.

The siege of Vienna, in 1529, was the first attempt by the Ottoman Empire to capture the city of Vienna in the Archduchy of Austria, part of the Holy Roman Empire. Suleiman the Magnificent, sultan of the Ottomans, attacked the city with over 100,000 men, while the defenders, led by Niklas Graf Salm, numbered no more than 21,000. Nevertheless, Vienna was able to survive the siege, which ultimately lasted just over two weeks, from 27 September to 15 October 1529.

A series of military conflicts between the Ottoman Empire and various European states took place from the Late Middle Ages up through the early 20th century. The earliest conflicts began during the Byzantine–Ottoman wars, waged in Anatolia in the late 13th century before entering Europe in the mid-14th century with the Bulgarian–Ottoman wars. The mid-15th century saw the Serbian–Ottoman wars and the Albanian-Ottoman wars. Much of this period was characterized by the Ottoman expansion into the Balkans. The Ottoman Empire made further inroads into Central Europe in the 15th and 16th centuries, culminating in the peak of Ottoman territorial claims in Europe.

The Ottoman Empire, also called the Turkish Empire, was an imperial realm that controlled much of Southeast Europe, West Asia, and North Africa from the 14th to early 20th centuries; it also controlled parts of southeastern Central Europe, between the early 16th and early 18th centuries.