Never, they are two different countries formed by slavs in middle ages.
Pan-Slavist (Nationalist) provocation by Russia!
No, Serbia was not part of Russia during World War 1. Serbia was an independent country that was allied with Russia during the war.
The Archduke of Austria Franz Ferdinand was assassinated by a Bosnian-Serb. In retaliation Austria-Hungary gave Serbia an Ultimatum of demands designed to destroy Serbia's influence in Bosnia. Serbia rejected the Ultimatum and Austria-Hungary declared war on Serbia. Germany was Austria-Hungary's ally and agreed to assist Austria-Hungary in the invasion of Serbia. Russia, fearing an invasion of Serbia would end it's own influence in the Balkans began to mobilize for war. As a result, Germany declared war on Russia.
Paraguayans declare their independence day on may 14 and 15 in 1811.
independence hall, philidephia
Because Russia is serbia's ally
Pan-Slavist (Nationalist) provocation by Russia!
Russia.
some guy from austria-hungary assassinated archbishop Ferdinand of Serbia. Serbia were allies of Russia and then Russia declared war on austria-hungary
Answer: Russia mobilized along the German border. Russia's mobilization amounted to a declaration of war. On August 1, German government declare war on Russia.
The assassination of Austrian Archduke Ferdinand was the immediate cause of World War I. He was killed by a Serbian terrorist, which caused Austria to declare war on Serbia. Serbia was allied with Russia, who intervened, causing Germany to declare war on Russia, which caused France to declare war on Germany.
Russia helped Serbia when Serbia had rebelled
Germany, Austria/Hungary, and Italy by the Triple Alliance!!
Well Serbia kill Austria-Hungary's beloved Arch Duke Franz Ferdinand. Austria-Hungary then declared war on Serbia; Russia (good alliance w/ Serbia after the helped Serbia declare their independence from the Ottoman Empire) stepped in to help & declared war on Austria Hungary. Germany (alliance to Austria Hungary) declared war on Russia and France (French had military agreement w/ RUssia). Then Germany invaded Belgium (Great Britain territory) to get to France, so great Britain got involved. THen the US saw the alliance powers were losing, so we sent them supplies and Germany sunk our ships, so the US joined in. Italy (alliance to Germany and Austria Hungary) saw the alliance powers were winning (France, Serbia, Russia, ect) and joined in to help them out.
ANSWER The main reasons were followings: 1 - because they were found humiliating and damaging the independence of Serbia; 2 - because Serbia was backed by Russia (which had pledged its intervention in case of Austria had attacked Serbia), in rejecting the demands.
Serbia
Russia was compelled to aid Serbia against Australia.