Second Balkan War - Outbreak of The War

Outbreak of The War

Further information: Order of battle of the Bulgarian Army in the Second Balkan War

The main Bulgarian attack was planned against the Serbs with their 1st, 3rd, 4th and 5th Armies, while the 2nd Army was tasked with an attack towards Greek positions around Thessaloniki. However in the crucial opening days of the war only the 4th Army and 2nd Army were ordered to advance. This allowed the Serbs to concentrate their forces against the attacking Bulgarians and hold their advance. The Bulgarians were outnumbered on the Greek front and the low-level fighting soon turned into Greek attack all along the line on 19 June. The Bulgarian forces were forced to withdraw from their positions north of Thessaloniki (except the isolated battalion stationed in the city itself which was quickly overrun) to defensive positions between Kilkis and Struma river. The plan to quickly destroy the Serbian army in central Macedonia by concentrated attack turned out to be unrealistic and the Bulgarian Army started to retreat even before Romanian intervention and the Greek advance necessitated disengagement of forces in order to defend Sofia.