Prior to World War I, the Russians and Austrians were feuding over control of the Balkans.
WWI was fought all over Europe. It spanned from western Europe, including France, Germany, and Italy, to the Balkans (the powder keg of Europe) and into Eastern Europe.
For centuries, the Balkans had been fought over by the Ottomans and the Austrians.
russia and austria-hungary were continually fighting over the 'balkans' during ww1.
The Ottoman Empire fought Austria-Hungary for control of the region.
France [i think]
Britain Apex<3
Christians and Muslims !
Christian and Muslim
Christian and Muslim
yes mostly. they have what you call western and eastern theatres
The conventional answer is Islamic and Christian people fought against each other. Most of the wars between Muslims and Christians were in Spain, but they also happened in Sicily, Italy, the Balkans and elsewhere. But there were also wars between Christians and pagans throughout most of the Middle Ages. There were wars between Catholic leaders of the Crusades and the Eastern Orthodox, and there were crusades against various heretical groups.
Russia tried to gain control but was only partially successful. Territories such as modern Armenia and Azerbaijan were once Ottoman but were lost to Russia. Much of the Balkans fought for independence from the Ottomans but didn't become Russian.