In the brief period before World War I, many political, cultural, and social factors combined to create the massive eastern conflict that dragged in half the globe and spawned the Bolshevik revolution.
Empires required lots of military power and economic growth to sustain, and required a state to produce this. Many of the great powers were centered around the idea of a balance of power between six great powers in Europe in two alliances, which generally prevented war. However, the massive shifts in the Balkans shook this balance, especially as nationalism came to the rise.
Germans feared the surrounding alliance between Russia, France, and England, just as Russia was sure to become a massive empire in time, owing to its vast human resources and land, especially in Siberia and Ukraine. If there was ever a military time to strike, it was now, which conflicted with their previous policy of peace between the related Nicholas II and William II, respective leaders of Germany and Russia, and the idea that imperial states required land. Land that was hard to find in Central Europe.
Meanwhile, public opinion cried out for the inevitable conflict between teuton and slav, notably the pan-slav paper Novoe Vremia. Although liberals in the bourgeouis and Duma explained that only a full democracy would sate the interests of the people, which was likely true, public opinion often wasn’t of much help either, being formed primarily by the elite. Conservatives claimed that allowing a democracry to take place would let in socialist radicals, and they too were probably correct. The average Russian farmed, and war would only take up needed helping hands.
And then there were the military in Russia who hungered for war as a chance to prove their worth, and a societal claim to fame that ignored faulty military preparedness. Also consider that the Duma was a newly created part of government, and the traditional monarchical structure placed a great deal of strain on the Tsar and his Ministers and slowed down action drastically. Russia’s mobility was a nightmare, as was their military strength.
Russia also had a long term plan to take the Straits and free the Slavs to become a pan-slav state, but there were many issues with this, not regarding that they only accepted Russian as the slavic language to be used and various conflicts inside the slav culture. Their best attempt at this in foreign policy was likely in the Balkan League with Serbia, but in the period before 1914, the Balkans and the dissolution of the Ottoman Empire was a bomb waiting to go off. When the Archduke Franz Ferdinand was assassinated by a rogue pan-slav group (The Black Hand), that allowed Austria to start a war before consulting with any of the other great powers.
Finally, none of the great powers expected a conflict to last this long, and it was well known that a drawn-out conflict would destroy the economies of Europe. What they didn’t know is that it would wreck the lives of millions of people on other continents and around the globe. One would hope that such a disaster would prevent another.
Whoof. That was long.