Ferdinand            Instability and weakness in the failing Ottoman Empire led to the First Balkan War in 1912, when Bulgaria, Serbia and Greece joined forces against the Turks in an effort to win back territory. Istanbul was almost taken by the Bulgarians, who did win back some of Thrace and Macedonia, but conflict between the three allies over the rest of Macedonia resulted in the Second Balkan War in the following year. Serbia and Greece soundly beat Bulgaria and took away more land, but Bulgaria did end up with the Pirin region of Macedonia as well as Thracian land all the way to the Aegean.

As World War I unfolded in the Balkans, the Bulgarian government - again with their eyes on Macedonia - hoped to fight little, yet gain much land. Pro-German Ferdinand and Prime Minister Radoslavov entered Bulgaria into the war on the side of the Central Powers, even though the general popular opinion was with Slavic relation Russia and its allies, Britain and France. Ferdinand eventually abdicated after a September 1918 army revolt and his son Boris III took control. After the terrible toll of the war itself, the Treaty of Neuilly in 1919 exacted even more from Bulgaria. Land was lost on all sides to Serbia, Romania and Greece, the army was restricted and huge war reparation payments were required.

Amid growing social discontent, two political groups that had formed in the late 1800's now gained strength. Representing the interests of peasants and the rural population, the Agrarian Party headed by Alexander Stamboliiski emerged victorious in the 1919 elections, with the Communist Party finishing a close second. Stamboliiski's policies were fairly radical, and he made many enemies with his "peasant power" reforms, such as dividing up large land estates. Nationalists were outraged by his plan to foster better relations with Yugoslavia and especially by his idea to drop all Bulgarian claims to Macedonia. The IMRO (Internal Macedonian Revolutionary Organization) was gaining strength at the time, fuelled by Macedonian refugees who had been pouring over the border into Bulgaria for decades to escape Serbian control. Extremists from the IMRO joined a right-wing army officer coup in June 1923, and before they assassinated Stamboliiski, they cut off the hand he used to sign the Treaty of Ni's with Serbia.

After the Agrarians and Communists staged an unsuccessful uprising in September 1923, a period of terror and anti-Communist sentiment reigned under the power of Alexander Tsankov, who was in control until 1931. The Communist party was outlawed, thousands were killed, and their leader, Georgi Dimitrov, along with many others, barely escaped to Russia. In 1926, an amnesty helped quell some of the disorder of the time, and the League of Nations sent financial assistance to help resettle the Macedonian refugees.

The 1930's saw several groups with differing agendas take control during the uncertain economic and political times of the Great Depression. On the heels of Tsankov's repression came the right-wing extremist Zveno ("Link") Military League, who took over and began a dictatorship in 1934, continuing the general trend across Europe towards more authoritarian control. Tsar Boris III followed suit in November 1935 and established himself as absolute monarch until 1943.