In the first chapter Mantegazza predicted the First World War, with two sides fighting bloody, immense naval and ground battles and with "one million deaths in a single day" near Paris. After this war, all nations unite to abolish war (" a war that killed all wars") and the "United States of Europe was founded", with a single idiom and a single currency, engendering peace for the succeeding two millennia. After almost a century of dictatorial domination, socialist regimes were replaced by democratic ones.