The short answer will be found by in the term “Secret Protectorates”. Too many nations had essentially said “I got your back” behind closed doors. I’m over simplifying the hell out of this, but it was like picking on the one kid and then he goes and gets 20 friends, but its okay because you have 20 friends too and then there is Playground War I…
That’s the elementary textbook type answer though. If you’re looking for the deeper political and economic causes I’ll have to leave that to somebody a bit more learned than myself.
Yeah, Serbs shot Archduke Ferdinand. Austro-Hungarians (A-H) declared war on Serbs (IIRC), who were protected by the Russians. (Or was it the French? Anyways, the French, English and Russians-the Triple Entente-were protecting each other.) The Triple Entente declare war on A-H. Germany was A-H’s protector and beat up on France.
Suggested reading: “All’s Quiet on the Western Front” for a look at what WWI was lik