How did napoleon create an environment in the countries he conquered and later ruled, that spurred an increase in nationalism?

Many Europeans saw Napoleon and his armies as foreign oppressors and fought back to save their countries.

Further detail:

As Napoleon's armies conquered other territories in Europe, he arranged new governmental districts that didn't align with previous territorial boundaries.  He did this so as to take away local and regional loyalties, trying to make all the conquered territories into departments of the French empire.  

A good example of Napoleon's conquests sparking nationalism in the conquered regions would be the various German lands.  The  German territories had been divided into hundreds of different kingdoms and principalities and independent cities.  Napoleon grouped them together into a number of administrative departments for his own purposes. German territories that had always maintained much separation from each other now were grouped together in ways that made them work with each other.  And guess what?  One of the biggest things they wanted to work on was getting rid of French occupation of their territories.  So in the long run, Napoleon's strategy backfired.  It helped to promote German nationalism, and in the following century, the German territories banded together to defeat France and establish the German Empire.

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