What was the cause of world war one and two

The first war was because the assassination of Archduke Franz Ferdinand of Austria-Hungary second was because Italian fascism in the 1920s.

Ibelieve the answer is water and oil.

Ongoing civil wars western roman empire finally collapsed476 c.e. romulus, the last of theroman  emperors in  the west, was overthrown by the germanic leader odoacer, who became the first barbarian to rule in rome. the order that the  roman empire  had brought towestern  europe for 1000 years was no more.