As the 18th century changed to the 19th century, the big question in Europe was this: what would the French Revolution lead to? Europe's rulers had good reason to be concerned. The social reforms in France had led to the destruction of aristocratic privilege and the execution of a king. If these reforms spread to other countries, the conservative regimes in power would suffer. As France increasingly became a meritocracy, the country became more efficient, powerful, and increasingly patriotic, with people at all levels of French society began to feel more of a stake in France's future. The power of the masses was starting to be tapped unlike ever before in history.
Napoleon, a minor Corsican aristocrat who rose to be Emperor of France, represented the new confidence in social mobility and individual talent the Revolution had wrought. Even if he was a dictator, Napoleon was still in many ways very progressive, advancing many of the goals of the Revolution, and rationalizing government and social processes wherever he went.
Nearly all of Europe fell under Napoleon’s control, and certainly all of it was forever changed in being ruled by him or fighting against him. Even as it spread conflict, Napoleon’s conquests also spread the new ideas and institutions of the French Revolution throughout Europe. The countries he occupied had versions of the Napoleonic Code imposed on them, forming the legal basis for much of Continental European law today. The liberal ideals of legal equality codified in his law system spread to his opponents as well, as Prussian reformers like Baron vom Stein and Karl August von Hardenberg realized that, in order to compete with France, they had to create a Prussian state that was like France.
Napoleon’s regime also helped mobilize nationalist movements. In reacting to their French overlords, some previously disunited linguistic-ethnic groups saw reason to organize and built nationalist movements, most notably in Germany. Germany even reacted intellectually, starting to champion Romanticism, a school of thought opposed to the French Enlightenment’s favored Rationalism. Interestingly, the Napoleonic Wars fueled the energies of both liberal and conservative opponents: in Spain, a bloody Peninsular War was fought by guerillas who wanted to return a Bourbon to the throne, while in Germany, people complained that they wanted more self-rule.
The Napoleonic period was an extremely complicated time. Napoleon was a dictator, but he also encouraged many developments we today consider quite positive. The Napoleonic Wars were instigated by France, but each nation fought to expand their own national interests as well, not just to defend themselves. The wars were also punctuated by constantly shifting alliances, with friends becoming foes and vice versa. The only constant through the 15 years of Napoleon's rule was the continued enmity between England and France. Instead of a war between irreconcilable values, the Napoleonic Wars were fought with essentially the same motivation driving all sides: greed.
If anyone won the Napoleonic Wars, it was Britain, emerging in 1815 as a commercial powerhouse with the world's preeminent navy and a large colonial network. British industry might have provoked working-class rebellion if not for the national unity that having an enemy like Napoleon provided. Blaming the hard lives of the working class on Napoleon's war mongering, Britain made it in one piece through a critical and dangerous time of its young Industrial Revolution.
The disorder Napoleon had created in Europe was cleaned up, as much as it could be, by the Congress of Vienna (1814-1815). The resulting agreement was undoubtedly one of the most important and complicated treaties in human history. The international order that the Congress designed had stability in mind, ensuring future rising powers could be stopped by coalitions of other powers. This also protected conservative regimes, who had been threatened by the liberal changes Napoleon has spread with his empire. Thus, the Congress of Vienna set the stage for the coming battle between liberalism and conservatism in the following period, from 1815 to the revolutionary year 1848.