The Expulsion of Albanians 1877–1878 refers to events of forced migration of Albanian populations from areas that became incorporated into the Principality of Serbia and Principality of Montenegro in 1878. These wars, alongside the larger Russo-Ottoman War (1877–78) ended in defeat and substantial territorial losses for the Ottoman Empire which was formalised at the Congress of Berlin. This expulsion was part of the wider persecution of Muslims in the Balkans during the geopolitical and territorial decline of the Ottoman Empire.