User blog comment:ChrisL123/No Franco-Prussian War??/@comment-32656-20120328060024

Chris, you're wrong about the factors. While that contributed, it was not the reason, by a long shot.

Bismarck, and the Prussian King - though, no mistake, definitely mostly Bismarck - wanted to unite the German states under their banner. The Southern states were obviously in the way of this. And, they could count on France to make sure it stayed that way, despite these same states being allied - though not very willingly, but allied nevertheless - with Prussia.

As such, in order to unite the Germans under their banner, the Prussians needed to beat France. Which, after cooking up a reason for the French to be stupid, they did.

The reason they cooked up, of course, was the Spanish Question, and the Ems Dispatch. Which, among other things, meant the French held no international support.