It is almost impossible to grasp the extent and the profundity of the changes which have been produced by the World War. To realize these is to see that all previous works of reference are now out of date, and to appreciate at a glance the justification and the necessity of this the first post-war Encyclopædia. Let us consider some of the more striking features of which a new compendium of knowledge must take account.
First, there is the history of the great conflict itself. This begins with the political system of Europe as it had been modified by the military and industrial developments of Germany since the defeat of France and the formation of the German Empire in 1870–1871. The diplomatic history of the last fifty years is now to be seen in a new perspective, and the events of the summer of 1914 especially demand study. The course of the actual fighting involves naval events in all the oceans, and land fighting from Flanders eastward to Vladivostok. The forces include the populations of countries hardly known previously to the Western nations, and economic and geographical features hitherto familiar only to specialists. The methods of warfare were throughout the struggle continuously developing, and science was making vast contributions to the agencies of destruction, as well as to the prevention and healing of disease and wounds. Great figures of the pre-war period suffered eclipse and new personalities emerged. Almost every branch of human thought was affected by the impact on the minds of men of the unexpected turn of events and by the unforeseen developments of the psychology of nations and of individuals. The treaties which brought the conflict to a formal close have modified the frontiers of half the countries of the world, and have produced an entirely new arrangement of economic forces; while inside the various countries the experiences of the war have produced far-reaching changes in industrial economy and the position of women.
This is but a sketch of some of the main considerations which show how unavoidable is the recasting of a work like the present which attempts to hold a mirror up to the world. The task of revision has been no easy one, especially since so much is still unsettled. But to follow the events that each day is still bringing forth men need to have accessible a precise account of what has happened in the last seven years.
In the attempt to render this service the editors of the present work have had the Great War itself treated in a compendious
