While the war dragged on, the internal political situation was rapidly deteriorating. The country was in a state of economic chaos, and the living conditions of laborers and peasants continued to decline. Farm production dropped quickly, resulting in famine and soaring prices. These dire conditions gave a strong impetus to the growing antiwar movement in the country. The movement was headed by the left-wing Socialists, who attempted to correlate the antiwar movement with socialist propaganda. The Russian Revolution of 1917 stirred some elements of the Bulgarian population who, like the Russian people, felt that their government failed to represent their interests and was unresponsive to their needs. There were open revolts in the towns and villages; underground activities were growing within the Bulgarian army itself. By 1918 Bulgaria and the Central Powers were defeated, leaving Bulgaria in a worse position than before the war. Hopes of regaining Thrace and Macedonia were dashed, and the country was immeasurably weakened by external fighting and internal division. The people were frustrated and bitter. Although the war had stimulated Bulgaria's industry--there were 345 industrial enterprises in 1911 and 1,404 in 1924--it had been costly in other respects. Bulgaria was forced to pay both reparations and payments for the allied occupation that followed. Taxes rose, and the value of the currency declined. As a result, King Ferdinand was forced to abdicate in 1918, shortly before the armistice was signed. The Treaty of Neuilly-sur-Seine was signed on November 27, 1919, ending Bulgaria's role in the war and establishing her boundaries. Once more Bulgaria had entered a war on the losing side, and once more its irredentist ambitions had resulted in no territorial gains. At the end of the war Bulgaria lost Thrace to Greece--thus failing in her attempts to gain access to the sea--and a small area in the Rodopi (or Rhodope Mountains) and a portion of its western frontier to Yugoslavia. As a result of these losses, Bulgaria was left with a still greater sense of frustration and hostility toward its Balkan neighbors. THE INTERWAR YEARS The period between the first and second world wars was one of political unrest and Macedonian terrorism. The country was in an almost untenable economic situation at the close of the war: prices skyrocketed, people died of starvation, and strikes were almost continuous. Out of this situation two extreme political groups grew up. On the extreme Right was a faction of the IMRO, which at that time demanded the annexation of Greek and Yugoslav Macedonia. On the Left was the Bulgarian Agrarian Union, the only party at the time more popular than the Communists.