If Europe was so 'peaceful' after 1815, why were there continued revolutions in France, Belgium, Spain, Prussia, Poland, and elsewhere in the 1820s, 1830, and 1848? And they were not merely internal, they were international.
Those facts seem to be overlooked when discussing Europe after 1815.
And if you wish to discuss any repressive measures used by Napoleon as head of state, they should be compared with the same type of measures in Russia, Great Britain, Austria, and Prussia. Napoleon still comes of better if actual research is done on the subject and not just bias and hyperbole. None of the countries in Europe were democracies, including Great Britain, and the monarchies of Russian, Prussia, and Austria were repressive in many more ways than Napoleon ever was in such areas as basic civil rights, freedom of religion, education as well as providing such institutions as hospitals and orphanages, as well as providing an atmosphere in the different countries with at least an opportunity for a better life or having the basics of life to survive.