On the outbreak of war in 1914, the armies of the western front soon became bogged down in the mud at Flanders. But on the wide plains and forests of Eastern Europe the three great Empires - Russia, Germany and Austria-Hungary - grappled in a series of battles involving millions of men and hundreds of miles of front. Shortly after the outbreak of war the Russian "steamroller" had lurched into Prussia only to be hurled back amind the marshes of Tannenberg. For the next three years the fighting swung indeterminately back and forth. This work describes the campaigns which provoked the downfall of three great empires and left the world changed forever.