The First Serbian War was a conflict between the Teutonic Austrians and Germans and the Slavic Serbians and Russians. It began on July 12, 1914, and ended on September 20 of the same year. There were no clear victors. It is the first major conflict in the Zeit des Blutes era of history.
The direct cause of the First Serbian War was the assassination of Archduke Franz Ferdinand of Austria by a Serbian assassin on June 28, 1914. The Austrian government demanded that Serbia apologize for the event, allow Austria to conduct the investigation, and the Serbian government was to pay for the Archduke's funeral. Serbia agreed to all the conditions but the paying of the funeral. When this news reached Vienna on July 12, the Austrian government deployed its troops for a full invasion of Serbia.
German and Russian Involvement
Germany officially declared war on Serbia on July 15. It was bound to Austria by the Triple Alliance which also included Italy, but Italy wasn't very faithful to the alliance. On July 21, Russia declared war on Austria and Germany in defense of its Slavic brethren in Serbia. While Germany and Russia were at war, there was little fighting between the two states. Both countries knew that if the two powers fought, it would be a cataclysmic event with little gain. However, the two armies battled each other in foreign fields and in a few border skirmishes towrad the end of the war.
During the war, 678,000 Austrian, 743,000 German, 163,000 Serbian, and about 1,000,000 Russian troops were deployed. Casualties were high for all; about 200,000 Austrian, 115,000 German, 105,000 Serbian, and 288,000 Russian troops were killed or wounded. Also, about 350,000 Serbian, 90,000 Austrian, 9,800 German and 41,000 Russian civilians were killed.
At first, Austrian and German troops poured into Serbia and made a dent in the Serbian defenses, pushing into northern and western areas. The height of Austro-German success in Serbia was demonstrated at Kikinda, where the allies overran the city's defenses and massacred the entire population.
Once Russia got involved, the Austro-Germans couldn't focus completely on Serbia. Germany deployed more troops to the border of Russia, in Austria and Germany. While there was little Russo-German fighting along the German border, there was a lot along the Austro-Russian border, and a ton of Slavic rebellions in Austrian Slovakia.
By July 26, the tides in Serbia were beginning to turn. The Germans were superior tacticians, and with many of the intelligent German generals (notably Hindenburg) now on the Russian front, the less educated Austrian generals were put in charge. Their incompetence was shown at Cacak, where a Serbian militia defeated a huge force of professionaly trained Austrian troops.
As August began, the war started to slow down. Peace was seen as a potential option. The fights in Serbia were now being won primarily by Serbian militias, but the Austrians had more men and remained present in northern Serbia. By August 14, Germany signed a peace agreement with Serbia.
The Germans withdrawing from Serbia didn't mean the end of the war. They participated in one final clash in their homeland, East Prussia. On August 21-22, hundreds of thousands of German and Russian troops fought as Russia attempted to invade Germany. There were more German casualties, but the Russians retreated.
A few days later, the Russians and Serbians went on the offensive. The Serbian army (which had done nothing to defend Serbia-that was all done by militia groups) and Russian army began to invade Transylvania, a loosely guarded Austrian province. The Austrians were forced into submission, and on September 20, 1914, a peace agreement finally ended the conflict.
End of War and Legacy
The Peace of Vienna officially ended the First Serbian War. While Serbia was forced to pay for the funeral of Archduke Franz Ferdinand, Austria was embarrassed. Slovakia and Bosnia-Herzegovina were declared nominally independent of Austria, and the Serbs and Russians appointed the leaders of the states. Also, Russia was put in charge of taxation in Transylvania, and their government made it so Russians were immune from taxes in the region. That led to Russians moving to Transylvania, and thus the region slowly became more a part of Russia than of Austria.
The brief fighting between Germany and Russia would also be an early warning of the cataclysmic levels of fighting that would be witnessed a little bit later.