Kingdom of Bulgaria (Twilight of a New Era)

The Kingdom of Bulgaria, also referred to as the Tsardom of Bulgaria, the Third Bulgarian Tsardom and the Third Bulgarian Empire (Bulgarian: Царство България, Tsarstvo Balgariya), was a constitutional monarchy. The Kingdom was bordered by Romania to the north, Serbia to the west, Greece and Turkey to the south, and the Black Sea to the east.

The state was almost constantly at war throughout its existence, lending to its nickname as the Balkan Prussia. For several years Bulgaria mobilized army of more than 1 million people from its population of about 5 million and in the next decade (1910–20) it engaged in three wars - the First, the Second Balkan War and the First World War. After this the Bulgarian army was disbanded and forbidden to exist by the winning side of the World War and all plans for national unification of the Bulgarian lands failed (Treaty of Neuilly-sur-Seine).

After the Third Balkan War, the monarchy was abolished, its final Tsar was sent into exile and the Kingdom was replaced by the Republic of Bulgaria.