The settlement of the Second Balkan War had also inflamed Bosnian nationalism. In 1914 that movement ignited an AustrianSerbian conflict that escalated into world war when the European alliances of those countries went into effect.
Supported by Ferdinand, the government of Prime Minister Vasil Radoslavov declared neutrality to assess the possible outcome of the alliances and Bulgaria's position relative to the Entente (Russia, France, and Britain) and the Central Powers (AustriaHungary and Germany). From the beginning, both sides exerted strong pressure and made territorial offers to lure Bulgaria into an alliance. Ferdinand and his diplomats hedged, waiting for a decisive military shift in one direction or the other. The Radoslavov government favored the German side, the major opposition parties favored the Entente, and the agrarians and socialists opposed all involvement. By mid-1915 the Central Powers gained control on the Russian and Turkish fronts and were thus able to improve their territorial offer to Bulgaria. Now victory would yield part of Turkish Thrace, substantial territory in Macedonia, and monetary compensation for war expenses. In October 1915, Bulgaria made a secret treaty with the Central Powers and invaded Serbia and Macedonia.
Data as of June 1992