Who started World War 1?

In my oppinion, Germany was the main cause of world war 1 because they had dictators as leaders. Bismark and Kaiser. It all started with Germany wanting more land and starting problems with each country. They fought France for no reason. This causing the countries to find allies and start to be scared. Then, Germany decided to start building a large army. That caused the other countries to become frightened and gang up. People think Austria-Hungary is the cause, but A-H only made all of those problems for Serbia because they had Germany to back them up. Again, Germany is the start.