The Kingdom of Serbia and WWI

On 1878 , the Treaty of Berlin was signed by the United Kingdom, Austria-Hungary, France, Germany, Italy, Russia, and the Ottoman empire. The signing of the treaty officially stated the complete independence and recognition of Serbia, Montenegro, and Romainia. The treaty also guaranteed the Autonomy of Bulgaria though it still remained formally under Ottoman administration. However, the traditionally Serbian lands of Bosnia and Novi Pazar remanied under Ottoman rule only later to annexed to Austria. On October 8, 1912 the Balkan League, consisting of Serbia, Bulgaria, Greece, and Montenegro, declared war on the Ottoman Empire. The League fought with the Ottomans and quickly defeated them and thus liberated Aegean Macedonia and todays FYROM. Soon after, the Second Balkan War was declared. The Bulgarians, unhappy with their gains from the first war declared war of Serbia and Greece. However, Serbia and Greece had signed a military pact before the Bulgars attacked. Also, Romainia and the Ottomans joined the war later on. The result was a Bulgarian defeat and the re-incorpoartion of Vardarska Banovina (Old Serbia) into Serbia. Aegean Macedonia was fully under Greek control. However, Ottoman rule was re-established in Ariadonople.

In Bosnia however, nationalist youth groups were still strong. A prominent group was called Young Bosnia. They were primarily Serbs and Muslim Serbs (Bosniaks). They were conspiring against the Austrian throne in an attempt to re-unify Bosnia with Serbia. On June 28, 1914, the Archduke Franz Ferdinand was shot and killed by Nationalist Gavrilo Princip outside a Sarajevo cafe. This spurred the Austrian ultimatum to Serbia. The Serbs accepted all but one of the terms in the ultimatum. The Austrian Empire deemed the response insufficient. Thus, they declared war on Serbia. The declaration of war caused a chain effect in Europe. Thus Russia, France, Britain, Germany, and many other European nations became involved. The Austrians attempted to invade Serbia by crossing the river Drina and the Danube. However, they were met with stiff resistance and lost some decisive battles. Notably, the Battle of the River Drina and the Battle of Cer. In 1915, the Austrians, seeing they could not defeat Serbia alone, decided to enlist the help of Germany and Bulgaria. The three nations invaded Serbia from all sides. However, General Putnik, instead of surrendering or fighting a hopeless fight, ordered an all out retreat through Montenegro and Albania. Later the troops would be transported to Corfu and Thessaloniki where they would regroup and return to action against the Triple Alliance six months later. After the Serbian troops were re-mobilized on the Greek front, they were on the defensive against Bulgarian troops. Steadily, the Serbs begain pushing the line up and though the Germans attempted to bloster Bulgarian forces the French-Serbian army succesfully captured Manastir. More and more Bulgarian troops began surrendering without a fight and the Serbs recaptured all of Serbia. The Corfu declaration was also signed which signalled the creation on the Kingdom of Serbs, Croats, and Slovenes.