Why was France given such a lenient peace after Napoleon was defeated?

Question

For two decades revolutionary France had attacked and conquered many nations in Europe. Millions were killed. But when the allies finally defeated France, the peace was very lenient. France didn't lose anything apart from what they conquered during the wars. Why were the allies so lenient towards France, which logically should have been a hated enemy? Especially since France was such a powerful enemy, shouldn't they want to weaken France?

Answer 1

In 1814, representatives of the powers who had defeated and exiled Napoleon Bonaparte met at the Congress of Vienna to arrange a lasting peace after - as you note - decades of devastating wars (of course, Napoleon would stage a brief comeback in 1815 while the Congress of Vienna was still in session, but the crisis passed in the wake of Waterloo).

The representatives identified two major contributing factors to the wars that had plagued Europe (and beyond). The first, of course, was the French Revolution, which had overthrown (and executed) the King of France, had replaced him with a - for its time - radical government that promoted liberty and equality for all people regardless of class, values that were promoted by French armies beyond the frontiers of France. The powers represented at the Congress of Vienna sought (in the long run, unsuccessfully) to put the genie back in the bottle by restoring the monarchy of France and pledging to support one another in upholding all monarchies and fighting against any attempts to put in place a Revolutionary democratic government (this mutual assistance in the fight against liberty was displayed, for instance, during the year of widespread upheaval in 1848, when Russian troops aided the Hapsburg dynasty in suppressing the uprising by the Hungarians),

The second major factor that the powers represented at the Congress of Vienna identified as causing the previous decades of wars was the power imbalance in Europe created by the increase of power of France, in terms of both territory directly annexed and territory indirectly brought under the control of France. As you noted, any territory that had been seized by France or had fallen under French control after 1789 was removed, so that France was returned to its former, Pre-Revolutionary borders.

By the same reasoning concerning the need for a balance of power in Europe in which no one kingdom had vastly more power that any of the others (which would at least offer the most powerful nation the option of using its power, particularly through the conduct of war, to further increase its power), France was not carved up and divided among the winners. If France was reduced in power, it would produce a vacuum of power that would inevitably be filled by another European kingdom, a kingdom that, at the expense of France, would grow so powerful as to upset the balance of power within Europe that the powers at the Congress of Vienna felt was vital for maintaining a state of peace.

Similarly, restoring the Bourbon dynasty to the throne of France ensured that the kingdom of France was not a threat to the stability of Europe. Unlike the Revolutionary Government and Napoleon Bonaparte, the Bourbon dynasty neither had expansionist aspirations nor was a threat to the other monarchies of Europe (one of the means by which France's ambitions were satisfied while not threatening the peace of Europe during the 19th century was French imperial conquests overseas in Africa and Asia).

Lastly, to further guarantee against any threat posed by aggression in Europe on the part of France, the powers represented at the Congress of Vienna also strengthened some of the victors, most notably the Kingdom of Prussia, which was awarded additional territory.

While the attempt by the Congress of Vienna to put the tooth paste of liberty and equality born out of the French Revolution back into the tube was ultimately a losing battle, the efforts of the Congress of Vienna to establish a balance of power among European kingdoms in order to prevent the outbreak of another European wide conflict was far more successful. While Europe experienced numerous wars between 1814 and 1914, most remained small in scale and none drew most or all of the kingdoms of Europe into a European wide struggle on the battlefield. It's no accident that the unification of German kingdoms into a single, tremendously powerful German Empire, a German Empire that threatened the balance of power established by the Congress of Vienna, was the single most important long-term cause of the outbreak of World War I.