How nationalism spread across europe with napoleon then repressed for a generation under the congress of vienna and concert of europe until the revolutions of 1845

Nationalism spread across Europe during Napoleon's time. It was repressed for a generation under the Congress of Vienna and the Concert of Europe until the revolutions of 1845/1845. The term "Nationalism" can be defined as a group of people with the same nationality should unite together under a single flag. Napoleon nationalised France and then moved across the rest of Europe, conquering  countries along the way. Eventually, Napolean was defeated and the Congress of Vienna was held by the heads of the European countries. The aim of these meeting was to ensure peace and stability in Europe. The revolutions of 1845/1848 overthrew the repressive European governments of the day.