The Vilayet of Kosovo was a first-level administrative division (vilayet) of the Ottoman Empire in the Balkan Peninsula which included the modern-day territory of Kosovo and the north-western part of the Republic of North Macedonia. The areas today comprising Sandžak (Raška) region of Serbia and Montenegro, although de jure under Ottoman control, were de facto under Austro-Hungarian occupation from 1878 until 1909, as provided under Article 25 of the Treaty of Berlin. Üsküb (Skopje) functioned as the capital of the province. Its population of 32,000 made it the largest city in the province, followed by Prizren at 30,000.