Belgium is one nation divided into 3 distinct regions; the largely Dutch speaking region of Flanders, the largely French speaking region of Wallonia and the bilingual Capital Brussels. Their is also a small German speaking region in the East/South East.
These regions all have individual governing bodies, with the power shared equally between them, I believe.
I have heard in numerous instances that there is great rivalry, and perhaps disdain between the French speaking region of Wallonia, and the Dutch speaking region of Flanders. Flanders holds much of the industrial factories and harbours, and is often considered to be quite wealthy in relation to the agricultural heartlands of Wallonia.
My question is simply, is there a call from the respective peoples to join the nations of the languages they speak? This would end the nation of Belgium and would result in expanded territories for France and The Netherlands, (Maybe Germany also). Or is it sort of a sibling rivalry, where their love for one another is hidden with petty arguments, and they both realise their is strength in unity.
This question basically requires 500 years of European history. I will attempted to keep the answer somewhat manageable.
In order not to go completely crazy we can start with the Seventeen Provinces. Again, keeping it simply, these are Provinces that all fall into the hands of the most influential dynasty in European history, the House of Habsburg. It covers basically what we now call Netherlands, Belgium and Luxembourg.
The Habsburg basically wanted to combine these provinces into some greater whole and rule them as sort of a section of their empire. They wanted these 17 provinces to be considered one thing, not 17 things. The idea being that not again would they be divided and given to different people of the next generation.
Even at that time this was a pretty rich region. Its location was strategic and very good for trade. So it was consider a very valuable and important part of the Habsburg lands. The problem was that these regions were comparatively modern, and didn't fit so well with the usual way of Habsburg rule. The elites were not always noble, but there was class of merchants and other non-traditional 'elites'. Even worse, the Reformation had happened and 'infected' specially the northern part of this region.
Philip II of Spain who inherited the Provinces, enacted policies that turned out to be perfect to make people angry, he suppressed Protestants. He demanded high taxation and continued to further unify the 17 provinces into one region. He also generally disliked the region and preferred Spain.
This lead to what is called the Eighty Years' War or the Dutch Revolt. As the name suggest, this was not a easy thing to deal with for many reasons. Mainly that Spain was doing lots of different stuff and other powers opposed Spain, specially Britain. At the end of this, the Northern Part of this region had made itself independent. While the southern, and more catholic, part remained part of the Hapsburg lands. This Southern Part includes Belgium.
This region then became disputed between France and Spain (Habsburg) and again jumping over lots of history, by the time of the revolution and the Napoleonic period it was taken over by France completely and simply absorbed into France.
As you can imagine, the powers that defeated Napoleon's France, specially Britain, absolutely did not want a powerful large France controlling the important ports channel ports. Britain never wants anybody, not Spain, not France, not Austria, not Germany to control these ports, and they pretty much opposed any great that held them for 100s of years.
During the Congress of Vienna they basically tried to go back to a unified model, created a larger Dutch republic as a powerful enemy that would limit future french expansion. Britain would have oppose this when the Dutch were still a serous power player, but now they prefer a larger nation. So basically the Southern Provinces was given back to the Dutch.
Problem was that while in theory Belgium should have been fully part of it and equal, the reality was different. The Southerm provinces had all kinds of discontent. They were still catholic, they didn't appreciate being treated like a colony (as they saw it at least). So after a few years in 1830 they revolted, the Dutch tried to prevent this in a interesting turn of history where now the Northern Part was trying to repress a Southern Revolt. The Dutch also could not managed it, and Belgium achieved independence. The 'Treaty of London' required Belgium to stay neutral and all great powers recognized it as such. This is the Treaty that was broken during WW1 by the Germans and brought Britain into the war.
So in summation, the Habsburg married everybody, basically inheriting lots of provinces in the North West of Europe. They could not keep control and lost it first to the Dutch Revolt and then to ever increasing French power. Eventual reintegration with the Dutch failed so Belgium and soon after Luxembourg turned into their own neutral countries.
Somebody else might tell more of the internal view, I have looked at the question from a great power perspective.
Sources:
Imprudent King: A New Life of Philip II
Army Flanders Spanish Road: The Logistics of Spanish Victory and Defeat in the Low Countries' Wars
The Wars of Louis XIV, 1667-1714
The Congress of Vienna and its Legacy: War and Great Power Diplomacy after Napoleon