Military Frontier

The Military Frontier (German: Militärgrenze, Hungarian: Katonai határőrvidék, Romanian: Granița Militară, Croatian: Vojna krajina), was a province straddling the southern borderland of the Habsburg Monarchy and later the Austrian Empire and the Austro-Hungarian Empire. It acted as the cordon sanitaire against incursions from the Ottoman Empire.

When created in the 16th century by Ferdinand I, the region was divided into two districts under special military administration: the Croatian Military Frontier and the Slavonian Military Frontier. Initially, the Military Frontier came under the jurisdiction of the Croatian Sabor and ban but, in 1627, it was placed under the direct control of the Habsburg military. For more than two centuries, they would retain complete civilian and military authority over the area, up to the abolition of the Military Frontier in 1881.

During the 17th century, the territory was expanded towards the East and new sections were created. By then, it stretched from Croatia proper in the west to eastern Transylvania in the east and included parts of present-day Croatia, Serbia, Romania and Hungary. During, this period, the defence system was also changed, from a conventional garrison model to one of 'soldier-settler' communities.