1. Introduction“The years of slavery are past, the Belgian rejoices once again; Courage finally gives him back the rights he had in the past, his leap will be strong and firm; Holding the ancient flag unfurled; to launch his message to the vigilant world: for the king, for law, for freedom”. (Belgian national anthem, 1830). This was what the Belgians sang when they fought for their independence, the song raises some questions about the situation in Belgium before there was a Belgian state or a Belgian nation. This article focuses on the national and state building of Belgium between the Middle Ages and 1830, since at that time Belgium did not exist, this article examines the situation in the territories belonging to present-day Belgium. The process of nation-state building in Belgium is explained by defining the concepts of nation and state, then analyzing the system of powers in the Belgian territory and, finally, stating whether or not Belgium was a state or a nation during the analyzed periods. .2. Key concepts2.1. Robert's State definition of a modern state is based on some characteristics, the ruler should be sovereign (supreme authority), have a defined territory, have legitimate power and be efficient.2.2. NationGellner defines it as a large body of people united by common descent, history, culture, or language, inhabiting a particular state or territory.3. Nation and state building of Belgium3.1. Middle Ages After the death of Charlemagne, the Carolingian Empire was divided into three parts by the Treaty of Verdun in 834. This division weakened the Empire, numerous battles took place and allowed the Viking invasions from the north. It was in that period that the hereditary character of feudalism and the power of the fiefdoms, in......middle of paper......anish were unable to centralize their territories but the Austrians had a centralized government which claimed to be absolute. It was only with the French invasion that Belgium was unified and part of an absolute, centralized republic. However, due to the balance of power, Belgium had to answer to the Dutch who were centralized and absolute but were not recognized by the Belgians due to the differences existing between the two nations, this led to the independence of Belgium. Belgium became a nation around the beginning of the 19th century because it was the first time they fought together to free themselves from people who did not have the same beliefs and history as them. Maybe they didn't speak the same language, French and Flemish, but they had the feeling of belonging together and as the Belgian motto says: l'Union fait la Force (Unity is strength)).