the royal air force carried out Action two bombing Attack raids Attack on sofia , the capital of bulgaria , in retaliation for the attacks Attack on yugoslavia , which ultimately surrendered Surrendering on 17 april .

in the resulting Causation treaty Sign_agreement of bucharest , bulgaria lost Earnings_and_losses most of the territories it had gained Getting in the first balkan war Military_operation in addition to being forced Motion to cede Surrendering the unk unk of unk province to romania .

the invasion Attack commenced Process_start with an overwhelming air attack Attack on belgrade and facilities of the royal yugoslav air force ( unk ) by the luftwaffe ( german air force ) and attacks Attack by german land forces from southwestern bulgaria .

unk greek civil war ( , `` o unk '' [ `` unk '' ] , `` the civil war '' ) was a civil war in greece fought Hostile_encounter between the greek government army ( supported Supporting by the united kingdom and the united states ) and the democratic army of greece ( dse ) UNK the military branch of the communist party of greece ( kke ) ( supported by yugoslavia , albania and bulgaria ) from 1946 to 1949 .

founded by the communist party of greece and supported Supporting by neighboring and newly founded Creating socialist states such as yugoslavia , albania and bulgaria , the democratic army of greece included Cause_to_be_included many personnel who had fought Hostile_encounter as partisans against german , italian and bulgarian occupation forces during the second world war of unk .

when romanian troops approached the capital sofia , bulgaria asked Request for an armistice , resulting in the treaty of bucharest , in which bulgaria had to cede portions of its first balkan war gains to serbia , greece and romania .

when romanian troops approached the capital sofia , bulgaria asked Request for an armistice , resulting in the treaty of bucharest , in which bulgaria had to cede portions of its first balkan war gains to serbia , greece and romania .