The Ottoman–Habsburg wars are fought from the sixteenth through the eighteenth centuries between the Ottoman Empire and the Habsburg (later Austrian) Empire, which is at times supported by the Holy Roman Empire, Kingdom of Hungary and Habsburg Spain.

The wars are dominated by land campaigns in Hungary (including Transylvania and Vojvodina), Croatia and Central Serbia.

By the sixteenth century, the Ottomans have become a serious threat to the European powers, with Ottoman ships sweeping away Venetian possessions in the Aegean and Ionia and Ottoman-supported Barbary pirates seizing Spanish possessions in the Maghreb.

The Protestant Reformation, the France–Habsburg rivalry and the numerous civil conflicts of the Holy Roman Empire serve as distractions to the Christians from their conflict with the Ottomans.

Meanwhile, the Ottomans have to contend with the Persian Safavid Empire and to a lesser extent the Mamluk Sultanate, which is defeated and fully incorporated into the empire.

Initially, Ottoman conquests in Europe make 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.

Later, the Peace of Westphalia and the Spanish War of Succession in the seventeenth and eighteenth centuries respectively leave the Austrian Empire as the sole firm possession of the House of Habsburg.

By this time, however, European advances in guns and military tactics outweigh  the skill and resources of the Ottomans and their elite Janissaries, enabling the Habsburgs to retake Hungary.

The Great Turkish War ends with three decisive Holy League victories at Vienna, Mohács and Zenta. The wars come to an end following Austria's participation in the war of 1787-1791, which Austria fights in alliance with Russia.

Intermittent tension between Austria and the Ottoman Empire will continue throughout the nineteenth century, but they will never again fight each other in a war and ultimately find themselves allied in the First World War, in the aftermath of which both empires are dissolved.

Historians have devoted most of their attention to the second siege of Vienna of 1683, depicting it as a decisive Austrian victory that saved Western civilization and began the fall of the Ottoman Empire.

However more recently historians have taken a broader perspective noting that the Habsburgs at the same time resisted internal separatist movements, and were battling Prussia and France for control of central Europe.

From a military historian's viewpoint, the tactics and techniques of the European armies proved decisive because the Ottomans troops were much too slow in responding, and failed to develop their own innovations.

The key advance made by the Europeans was an effective combined arms doctrine in which the infantry and artillery, supported by the cavalry, cooperated together to be triply effective.

The Ottomans continued brute force frontal attacks that were unable to defeat smaller European armies.