Answer :
1914, after the duche of Austria is shot dead in Serbia. That ignited 1st world war, but did not cause world war 1.
The main cause of world war 1 is for secret alliance formed between nations. When Austria declare war on Serbia, Russia comes in to side with Serbia, then Germany joins Austria, and so on. It became a big mess that was never intended that way.
The main cause of world war 1 is for secret alliance formed between nations. When Austria declare war on Serbia, Russia comes in to side with Serbia, then Germany joins Austria, and so on. It became a big mess that was never intended that way.