 Complete the following phrase:  The causes of the Franco-Prussian War are strongly rooted in the events surrounding the gradual march toward the unification of the German states under Otto von Bismarck. In the midst of the Austro-Prussian War of 1866, the Empress Eugénie, Foreign Minister Drouyn de Lhuys and War Minister Jacques Louis Randon, worried that a Prussian victory might jeopardize Frances status as the domit power in Europe, gained after the 