Bismarck's War by Rachel Chrastil
7 out of 10

Under Napoleon Bonaparte, France's "1st Empire" was heavily destructive in Central Europe.  Decades later, in 1870, France was in its "2nd Empire" phase, and Germany did not yet exist as a unified state.  Led by the Prussians and the political savvy of Otto Von Bismarck, many German duchies and principalities pushed for war with France to prove their collective might.

The war lasted only six months.  At first, it was intended to be a standard military conflict, but citizens on both sides caught nationalistic fever--resulting in social identities that would last into the 20th century.