Bulgaria, despite being small in size in the Balkan region, did make marking effects on the war. Even in the first months of its inclusion in the war, they had already taken over strategically important land in modern-day Macedonia, in the old Serbian lands. They main weaponry used was the Mannlicher rifle, in several of its forms, such as the 1886 and the 1884 model, created by the Austro-Hungarian military and used by several parts of the army. Other weapons included machine guns such as the Maxim guns, which were extremely useful in trench warfare. During the later years of the war, however, the Entente gained a strong technological advantage over countries such as Bulgaria, and could not be matched anymore.
There were several battles in which Bulgaria was involved with, every one of them being a prime example of the bloodiness of the first World War. One war in which Bulgaria was involved with, and one of the most remembered and important ones, was the Doiran War, which took place over the course of 3 years. It was a defensive position of Bulgaria against the United Kingdom’s offense, and the successful trench warfare resulted in the retreat of the UK forces in the area after spending 100,000 bomb shells to weaken trenches, then unsuccessfully trying to take control of that area. The British lost 12,000 men to the attack, while Bulgarians only lost 2,000. Another important battle was the Kosovo Offensive, which was an attack on the part of the bulgarians in Serbia which led to the retreat of Serbian troops in the end of 1914. This gave territorial control to Bulgaria and allowed them to continue their attack into Serbia and Macedonia. The Serbians lost over 30,000 men. The turning point to end Bulgarian successes in WWI was the Battle of Dobro Pole, which demoralized the army and led to an increasing number of desertions, resulting in the Armistice in 1918 signed by the Bulgarian government. The Battle of Dobro was between two strategically located areas which would have allowed Allies to reinforce other conflicts in the Balkan region. Bulgaria, however, was left without support after the retreat of its allies and the reluctance of Hindenburg to support the defensive movement, so they were greatly outnumbered and forced to flee. Even when the Bulgarians successfully defended Doiran later, they were so heavily demoralized that they fled the war to try and protect their land and deserted the army due to political unrest.