During the Great Turkish War (1683–99), in October 1689, a small Habsburg force under Margrave Ludwig of Baden breached the Ottoman Empire and reached as far as Kosovo, following their earlier capture of Belgrade. Many Serbs and Albanians pledged their loyalty to the Austrians, some joining Ludwig's army. A massive Ottoman counter-attack the following summer drove the Austrians back to their fortress at Niš, then back to Belgrade, then finally back across the Danube into Austria.