Treaty of Madrid (1526) in the context of "County of Flanders"

The County of Flanders was one of the most powerful political entities in the medieval Low Countries, located on the North Sea coast of modern-day Belgium and north-eastern France. Unlike the neighbouring states of Brabant and Hainaut, it was within the territory of the Kingdom of France. The counts of Flanders held the most northerly part of the kingdom, and were among the original twelve peers of France. For centuries, the economic activity of the Flemish cities, such as Ghent, Bruges and Ypres, made Flanders one of the most affluent regions in Europe, and also gave them strong international connections to trading partners.

Up to 1477, the core area under French suzerainty was west of the Scheldt and historians call this "Royal Flanders" (Dutch: Kroon-Vlaanderen, French: Flandre royale). Aside from this, the counts, from the 11th century onward, held land east of the river as a fief of the Holy Roman Empire, and this is referred to as "Imperial Flanders" (Rijks-Vlaanderen or Flandre impériale). From 1384, the county was politically united to the Duchy of Burgundy, and it formed the starting point for more acquisitions in the area, and the eventual creation of the Burgundian Netherlands. The expansion of Flemish ("Burgundian") power deep into the Holy Roman Empire further complicated the relationship between Flanders and France, but reinforced the connections with Brabant, Hainaut, Holland and other parts of the Low Countries. The link to the empire was strengthened even more when the Burgundian Netherlands came into the hands of the imperial Habsburg dynasty in 1477. Most of Flanders became part of the empire after the Peace of Madrid in 1526 and the Peace of the Ladies in 1529, although it came to be ruled under the Habsburg crown of Spain. The territories of the old county are now the only part of the late medieval French kingdom outside of modern-day France, Catalonia having been renounced in 1258.