Roman Gaul and the Low Countries

The area of modern Belgium was part of Roman Gaul and was later settled by Germanic Franks. In the Middle Ages, the region of the Low Countries (which included modern Belgium, the Netherlands, and Luxembourg) prospered as a center of trade and textile production, comprising powerful counties and duchies like Flanders and Brabant. Cities like Bruges and Ghent became major commercial hubs.

The Spanish and Austrian Netherlands

The Low Countries eventually passed into the hands of the powerful Habsburg dynasty in the 15th century. When the northern provinces successfully rebelled against Spanish rule during the Eighty Years' War (1568–1648), the Catholic southern provinces (modern Belgium and Luxembourg) remained under Spanish control. They became known as the Spanish Netherlands, and later, the Austrian Netherlands after the War of the Spanish Succession in the early 18th century. 

Independence and the Monarchy

After the Napoleonic Wars, the Congress of Vienna in 1815 merged the southern and northern provinces to form the United Kingdom of the Netherlands to create a strong buffer state against France. However, religious and political differences quickly caused friction. 

In 1830, the southern provinces revolted in the Belgian Revolution. The new independent Kingdom of Belgium was established and was recognized as a neutral state by European powers. A German prince, Leopold of Saxe-Coburg-Gotha, was invited to become the first King of the Belgians, King Leopold I, in 1831, establishing a constitutional monarchy. 

Congo Colony and the World Wars

Belgium quickly industrialized, but its most controversial period was the private colonial exploitation of the Congo Free State under King Leopold II, a brutal regime marked by severe human rights abuses. The territory was transferred to the Belgian state in 1908 and became the Belgian Congo. 

Despite its declared neutrality, Germany invaded Belgium in both World War I and World War II, leading to the country being a major Western Front battleground during WWI. 

Post-War Era and Federalization

After World War II, Belgium abandoned neutrality and became a founding member of NATO (headquartered in Brussels) and the European Economic Community (EEC), the precursor to the EU. Brussels has since become the de facto capital of the European Union. 

Modern Belgian history is increasingly defined by internal political and cultural tensions between the Flemish North and the Walloon South. This led to a series of state reforms, transforming Belgium from a unitary state into a complex federal state with significant autonomy granted to its linguistic regions and communities