The growing military, political and socio-economic costs for all belligerents as the Great War entered its fourth year were increasingly evident, liberal democracies and authoritarian states alike having to remobilise public opinion for yet greater sacrifices. While the Western Front was facing these challenges, 1917 was also marked by the collapse of Tsarist Russia and by food riots resuting both from the Entente's blockade of Central Europe and the revival of unrestricted submarine warfare by the Central Powers. Ottoman Turkey was feeling the strain of war as well, as British forces advanced in both Palestine and Mesopotamia. For states as yet uncommitted to war, such as the United States and China, 1917 was a year of decision. This volume amply illustrates the significance of this crucial year in the global conflict.