Why did Napoleon cause instability in Europe?

Napoléon Bonaparte was a Corsican statesman and military leader who rose to prominence during the French Revolution and led several successful campaigns during the French Revolutionary Wars. He was Emperor of the French from 1804 until 1814 and again briefly in 1815 during the Hundred Days. Napoleon dominated European and global affairs for more than a decade while leading France against a series of coalitions in the Napoleonic Wars. He won most of these wars and the vast majority of his battles, building a large empire that ruled over continental Europe before its final collapse in 1815

Following the radical French Revolution of 1789, First Consul of France Napoleon Bonaparte launched a series of military campaigns aimed at expanding the French Empire known as the Napoleonic Wars. The wars were largely successful for the French army until the overzealous French general attempted an attack on the Russian Empire, resulting in his army's defeat and Napoleon's exile to the island of Elba. His exile however proved ineffective, and Napoleon returned to the French throne and attempted further armed conflict in the continent. This time, Napoleon's forces were easily overwhelmed, and Napoleon was exiled to the remote island of St. Helena, where he would reside until his death in 1821. Meanwhile, as a result of the aggressive expansionist French campaigns, the Great Powers of Europe, which at the time was comprised of Great Britain, Austria, Russia, Prussia, and France, held the Congress of Vienna in 1814-1815 headed by Austrian statesman Klemens von Metternich to debate how Europe was to be reformed and how France was to be punished for its aggression. The Congress' first objective was to ratify the previously drafted Treaty of Chaumont, which forced France to cede any territory gained in the Napoleonic Wars and pledged each nation's army to resist and extinguish any continued French aggression. The second and more delicate objective of the Congress of Vienna was to size and reshape national boundaries in continental Europe in order to balance the Great Powers of Europe, using Northern Italy, Poland, and a series of small German states as a sort of neutralizing buffer between Austria, Prussia, and Russia. The ultimate result of the Congress of Vienna was the Concert of Europe-the framework for European international policy until the outbreak of World War I in 1914