Grenz infantry or Grenzers (Croatian: Krajišnici or Graničari) were light infantry troops who came from the Croatian and Transylvanian Military Frontier in Habsburg Monarchy (later the Austrian Empire and Austria-Hungary). This borderland formed a buffer zone between Christian Europe and the Ottoman Empire, and the troops were originally raised to defend Austria against the Ottoman Turks. When there was no danger of war against the Ottomans, the Grenzer regiments were employed by the Habsburgs in other theatres of war, although one battalion of each regiment would always remain guarding the border.