Inspired by Italian and German unification movements and Polish plans for a Europe of free, smaller nations, pan-Serb and pan-South Slav unification ideas emerged in the 1830s and 1840s. They gained a new momentum in the 1860s under the leadership of Prince Mihailo Obrenović, whose reign saw the departure of the last Ottoman troops in 1867. Formally independent following the Eastern Crisis of 1875-1878, Serbia became Austria-Hungarys satelite. The first modern political parties, socialist-inspired, pro-Russian Radicals, and Liberals, formed. A violent overthrow of dynasty in 1903 saw the return of a Karadjordjević monarch and coincided with important political developments in the Balkans, including a greater collaboration between Serbia and Habsburg South Slavs. The 1912-1913 Balkan Wars practically ended the Ottoman rule in Europe. Serbia doubled-up its territory, albeit by incorporating mostly non-Serb populated regions which had once been part of medieval Serbia. The 1914 assassination in Sarajevo of the Habsburg heir by a Serb and Yugoslav radical youth from Bosnia led to Austria-Hungarys declaration of war against Serbia, and to the beginning of the First World War.