with the rest of Bosnia Vilayet (Ottoman Empire's westernmost administrative division), was occupied by Austria-Hungary. The Ottoman Empire's handover of its Bosnian Vilayet to the Austro-Hungarian Army took place under the auspices of the 1878 Treaty of Berlin agreed by the United Kingdom, Austria-Hungary, France, Germany, Italy, Russia, and the Ottoman Empire as part of the Congress of Berlin, a conference organised in the wake of the 1877–78 Russo-Turkish War. Although the Bosnia Vilayet de jure remained part of the Ottoman Empire, it was de facto governed as an integral part of Austria-Hungary with the Ottomans having no say in its day-to-day governance. This lasted until 1908 when the territory was formally annexed and turned into a condominium, jointly controlled by both Austrian Cisleithania and Hungarian Transleithania. Background The Berlin Treaty was imposed by the Great Powers (Austria-Hungary and Russia, in particular, both of whom had major geopolitical interests in the Balkans) upon the rapidly dissolving Ottoman Empire, which entered the negotiations from an overwhelming position of weakness having seen many of its former territories achieve de facto independence over the previous half-century and having just been defeated in the year-long Russo-Turkish War that came on the heels of a number of uprisings among the ethnic populations living within the Ottoman borders. Eastern Crisis 1875–78 Previously, the Ottoman position in their Bosnia Vilayet had been weakened by the 1875–78 Herzegovina Uprising, an armed revolt by the local ethnic Serb population that began in the Herzegovina region in July 1875 before spreading to the rest of the vilayet. The uprising lasted more than two years before the Ottomans, aided by the local Muslim population, managed to put it down. During the fall of 1875, inspired and spurred into action by the Serb uprising in the Bosnia Vilayet as well as the Ottoman initial inability to put a stop to it, the exiled Bulgarian revolutionaries operating out of the neighbouring United Romanian Principalities (another de jure Ottoman vassal which was steadily moving towards independence) began planning for their own uprising which began in the spring of 1876. The Ottoman reaction to the Bulgarian insurrection was swift and brutal, leading to many atrocities as well as universal international condemnation as the uprising was put down within months. Another Great Power, the dual monarchy of Austria-Hungary, closely followed the events of the 1875 Serb peasant rebellion in Bosnia. Shaped by the Austrian-Hungarian foreign minister,