In theory, yes they could. Probably not before 1648 and probably not all of it (they would have to share some of it with France, just like France got Artois, Dunkirk, etc OTL).
I would say that the biggest problem would be that after a while, they stopped caring about it. They could have continued the war against Spain after 1648 and capture more of the Southern Netherlands than OTL, but most towns and provinces simply did not care enough.
I wopuld say that the stadholders in general wanted to expand Dutch territory, while the regents (often rich merchants or people who were connected to them) did not care about expansion in the Netherlands and just wanted to get richer (and thus needed peace to accomplish it). The rivalry of Maurice and Oldenbarneveld is a good example, but another one would be Willem II who wanted to divide the Southern Netherlands with France, while the regents, especialy those of all powerful Amsterdam did not want a war. In a way you see the same thing with the first Dutch Willem I, who was basicly a glorified stadholder was the one who finaly managed to get the Southern Netherlands.I first encountered this at High School. Back then I was interested in Dutch trade companies and came across what was a rivalry between Maurits and Oldenbarnevelt. I was interested and found out that Maurits had an ambition to conquer the remaining Spanish Netherlands. Oldenbarnevelt in favor of peace and trade.
Lately I was busy with an ATL for the Ottomans. But I want to change the events in some part of the world as well, The Netherlands for one. So I wondered if I could have the Dutch rebels to conquer all of the Low Lands or at least the Dutch speaking part. Ofcourse being a Dutchie this sounds favorable to me
As far as I know, after the death of Maurits there was a little interest to take over all. And after the agressive French policies the goal to conquer the South was as good as gone in favor of a Bufferzone against Louis XIV.
I wopuld say that the stadholders in general wanted to expand Dutch territory, while the regents (often rich merchants or people who were connected to them) did not care about expansion in the Netherlands and just wanted to get richer (and thus needed peace to accomplish it). The rivalry of Maurice and Oldenbarneveld is a good example, but another one would be Willem II who wanted to divide the Southern Netherlands with France, while the regents, especialy those of all powerful Amsterdam did not want a war. In a way you see the same thing with the first Dutch Willem I, who was basicly a glorified stadholder was the one who finaly managed to get the Southern Netherlands.
In the timeline I am planning, my plan is for (stadholder) Willem II to make a deal with the French to divide the Southern Netherlands by having him win the confrontation with Amsterdam and the other regents. Mind you, this would not give the Netherlands all of the Southern Netherlands (or in reality even all of Flanders).
A Dutch southern Nederlands/Flanders is the nightmare of the Hollandic (and especially Amsterdam) Regents. It would mean that Antwerpen could not be blockaded anymore. The port of Antwerpen is far superior to any other port in the Netherlands. Because of the shallow Zuyder Zee East Indiamen could not even get to Amsterdam.
A Dutch Flanders will break the Hollandic dominance of the Republic.
A good reason to add them, especialy for the stadholder.A Dutch Flanders will break the Hollandic dominance of the Republic.
Sounds interesting, no?
However, does one really want ones beating heart so close to the border with the French?
A good reason to add them, especialy for the stadholder.
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Mind you, there is one thing I would like to add. Antwerp will be part of Brabant, thus be a generality land and not a province. Most likely Holland would remain the most powerful province if Antwerp, or even if Flanders and all of Brabant were added to the Dutch Republic.
Once the Stadholder is in control he might very well decide to accept Brabant as a province to act as a counterbalance to Holland. A hurdle will probably the religion but would the Stadholder care as much as the Regents?
There is also the question of the Flemish 'diaspora'. Antwerpen fell to the Spanish in 1585 and 60,000 Antwerpian protestants left the city for the North. Will they return if the city is Dutch again?