The Franco-Prussian War was a conflict between the Second French Empire of Louis Napoleon (Emperor Napoleon III) and the German states of the North German Confederation led by the Kingdom of Prussia. There is no question that Prussian Chancellor Otto von Bismarck and the King of Prussia deliberately provoked the French into declaring war on Prussia in order to draw four independent southern German states—Baden, Württemberg, Bavaria and Hesse-Darmstadt—into an alliance with the North German Confederation dominated by Prussia thus bringing about a new united Germany with Prussia as the leader. Bismarck had been planning this for years. This was the plan and it worked perfectly. By 1900, Berlin had created a new Germany led and dominated by the Prussian government in Berlin.
A Mighty Fortress: A New History of the German People,
Gordon A. Craig,
The best overall study of rivalry between European powers during this time:
Alan J. P. Taylor,
The Struggle for Mastery in Europe: 1848-1918,
Oxford University Press,