This is a picture of a political map of europe in It depicts the lines defining the states. It also shows what states were in the Triple Entente(blue), Triple Alliance(purple), and Russian allies(green).
Alliances were a large part of World War One. The Triple Alliances consisted of Germany, Austria- Hungary and Italy. Another alliance group was the Triple Entente which consisted of Britain, France and Russia.
When Gavrilo Princip assassinated Archduke Franz Ferdinand of Austria on June few could have known it would reverberate for four years of brutal war, leading to the fall of three European empires and revolution in what would become the Soviet Union.
To Hell and Back: Europe 1914-1949 by Ian Kershaw. Even those who know the history well will find much to shock them in these pages. They will find much to enlighten them too, for it is not just a catalogue of horrors, but also a rigorous analysis of causes.