15/9/1918 The Vardar offensive: Allied breakthrough against the Bulgarians

The Balkan theatre has remained relatively quiet since Serbia was overrun in 1915. The Allies established a military base in Salonika in Greece but were unable to expand much beyond it, while other priorities meant that the Central Powers left the Salonika force largely unmolested. Even the entry of Greece into the war on the Allied side did not obviously make much difference to this deadlocked front.

This apparent stasis masks a fundamental change in the balance of forces in the Balkans. The Allies have been building up their strength while that of their enemies has been eroding. German troops were withdrawn to take part in the Western Front battles, leaving the line to be held mainly by the Bulgarians, with some Austro-Hungarian units in support. The Bulgarians fought well during the conquest of Serbia but since then their morale has fallen as their homeland has been gripped by food…