Dušan had grand intentions to hold Belgrade, Mačva and Hum, conquer Durrës, Phillipopolis, Adrianople, Thessalonica, and Constantinople, and to place himself at the head of a grand crusading army to drive the Muslim Turks from Europe. His premature death created a large power vacuum in the Balkans, that ultimately enabled Turkish invasion and Turkish rule until the early 20th century. While mounting a crusade against the Turks, he fell ill (possibly poisoned) and died of a fever on 20 December 1355. He was buried in his foundation, the Monastery of the Holy Archangels near Prizren.