Principality of Bulgaria

State · 1880–1944 CE · at its largest around 1917 CE

An autonomous Bulgarian state under Ottoman suzerainty created by the 1878 Treaty of Berlin, which declared full independence as a kingdom in 1908.

On its lands while it lasted

Sofia (c. 1880 CE): Capital of Principality of Bulgaria (1880–1908), Kingdom of Bulgaria (1947–1947), People's Republic of Bulgaria (1948–1990), and 1 more.
End of the Ottoman Empire (1922 CE): The Ottoman sultanate was abolished in 1922 and the Republic of Turkey was proclaimed in Ankara in 1923; the caliphate was abolished in 1924.