Serbian engineers in front of an artillery fortress, early WW1.

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Serbian engineers in front of an artillery fortress, early WW1.
Bulgarian Collapse Begins
Tsar Ferdinand of Bulgaria (1861-1948, r. 1887-1918). He agreed to ask for an armistice on September 25, likely in full knowledge that his days as Tsar were numbered.
September 25 1918, Gradsko--The German and Bulgarian plan for a limited retreat, followed by an attack on both sides to cut off the expanding Allied salient, quickly fell apart in practice. On September 25, the Allies took Gradsko, at the confluence of the Crna and Vardar, splitting the defenders’ armies in two and capturing a major supply dump (though the Germans burned much of it before leaving). The Bulgarians continued to put up a stiff resistance before Veles, further up the Vardar, with a fresh division, but any additional retreat would push them further and further away from Bulgaria proper, which the British entered on the same day (near Kosturino, now in Macedonia). The fall of Gradsko severely alarmed the Austrians and Germans, who finally began to send reinforcements to the area, but they would come far too late.
Meanwhile, as Franchet d’Esperey had ordered, the cavalry was unleashed. On September 25, they reached the Babuna Pass from Prilep (which they had captured without opposition two days earlier, just four days after a major German-Bulgarian military conference there). Its commander, Jouinot-Gambetta, then decided to strike through unforgiving but undefended country straight north towards Skopje, rather than proceeding immediately into the Vardar river valley to assist with the capture of Veles. The rough terrain meant the cavalry had to dismount, but they still advanced 11 miles on the first day.
The Bulgarian Army was falling apart. The country had been at war, on and off, since 1912, and had little appetite to continue the fight. Following the Russian example, Soviets were set up in several locations across the country. Troops began to desert en masse, some commandeering trains to return home, while others marched on Kyustendil, the location of the Bulgarian GHQ, in an attempt to end the war more directly. That night, hoping to avert a revolution, Tsar Ferdinand, under pressure from moderate political leaders, released the agrarian leader Stamboliski (a move he would almost instantly regret) and agreed to let his chief of staff ask for an armistice; his representatives would be received by the British the next morning.
Today in 1917: Lloyd George Visits France Today in 1916: Battle of Morval Today in 1915: Allies Begin General Offensive in Artois and Champagne Today in 1914: Germans Advance Near Saint-Mihiel
Sources include: Alan Palmer, The Gardeners of Salonika.
Serbian soldiers in a rest camp close to the front line somewhere in Serbia during World War 1.
Source: Library of Congress.
Zivorad Radojkovic, a member of the Serbian Cavalry.
Captain Dojčin A.Stanković. He was the commander of the 3rd company of the second battalion of the Danube division.
Serbian militia, 1914-15.
Serbian reservists, 12 December 1915.
Serbian soldiers being vaccinated, 1915
A French major is administering a vaccination against cholera to Serbian soldiers in 1915. Agence Rol: Major français vaccine les soldats serbes contre le choléra, black-and-white photograph, France, 1915; source: Gallica, Bibliothèque nationale de France, Rol 45629, http://gallica.bnf.fr/ark:/12148/btv1b69090635.