This is compounded by changing historical arguments over time, particularly the delayed availability of classified historical archives, and differing geographic zeitgeist then prevailing. The deepest distinction among historians is between those who focus on the actions of Germany and Austria-Hungary as key and those who focus on a wider group of actors. Secondary fault lines exist between those who believe that Germany deliberately planned a European war, those who believe that the war was ultimately unplanned but still caused principally by Germany and Austria-Hungary taking risks, and those who believe that either all or some of the other powers, namely Russia, France, Serbia and Great Britain, played a more significant role in causing the war than has been traditionally suggested.