 Between 1912 and 1918 , Bulgaria became involved in three consecutive conflicts — two Balkan Wars and World War I. After a disastrous defeat in the Second Balkan War , Bulgaria again found itself fighting on the losing side as a result of its alliance with the Central Powers in World War I. Despite fielding more than a quarter of its population in a 1 @,@ 200 @,@ 000 @-@ strong army and achieving several decisive victories , at Doiran and Dobrich , the country capitulated in 1918 . The war resulted in significant territorial losses , and a total of 87 @,@ 500 soldiers killed . More than 253 @,@ 000 refugees immigrated to Bulgaria from 1912 to 1929 due to the effects of these wars , placing additional strain on the already ruined national economy . 
