In the whole messy mess, Germany seems the driving force and the most aggressive. Just like the Austrians wanted a war to bring down the troublemakers in their empire (the Serbs) The German wanted to bring down again France which was becoming again a dangerous power which had allied with Russia, creating an alliance that threatened Germany on both sides at once. So when the Austrian Archduke was murdered by a Serb the Austrians took advantage of that to turn on the Serbs who had been making a lot of trouble in the Austrian-Hungarian empire and Germany started invading and declaring war right and left.
They thrashed thoroughly Belgium and north of France, destroying the fields and industries, treated so badly the civilian population that during WWII the threat of German occupation sent hundred of thousands people on the road in terror to escape them, were directly or indirectly responsible for millions of dead men and many, many people considered at the time it was only fair that they ... more.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.