|List of Roman kings of the HRE|
|Nations that joined the HRE later: Poland | Prussia|
|Nations that left the HRE: Bohemia | Florence | Switzerland|
|Nations that became defunct|
In the 13th century, the later Netherlands were still split into many smaller states, of which Holland was the most important one. One ruler of them, Wilhelm of Holland, who died in 1256, made it Roman king.
In the year 1287, a great flood swallowed lots of lands in the Netherlands, creating the Zuider Zee, which made it possible for Amsterdam to become an important harbor later.
Later in the century, the Netherlands had to suffer under various famines. In 1391, a group of radical Begines (a religious movement) toppled the bishop of Utrecht in the Eastern Netherlands, working together with his peasants. Although they were relatively peaceful, and probably couldn't have lasted in a war, the stupid bishop managed to anger all his potential allies in the area (the Netherlands were divided between Holstein-Holland-Hennegau, Luxemburg-Limburg, Brabant, Geldern and the (quasi-)republics of Flanders and Frisia at this time). So the new republic continued for a while, until in 1401 Holy Roman Emperor Gerhard I of Holstein crushed it, adding it to his empire.
Rise to kingdom
In 1414, Holland (important for its trade) got the eighth electoral vote in the Holy Roman Empire. In the same year, England under king Richard III made alliances with Castille and the Netherlands, to attack France again. A bit later, in 1419 Roman king Gerhard II was crowned emperor and also appointed himself king of the Netherlands, with the pope's OK. 1421, France made a separate peace with the Netherlands, giving emperor Gerhard Flanders, which was incorporated into the Netherlands too.
1430, emperor Gerhard died. His lands were divided: His older son Gerhard III became king of the Netherlands and Roman king, Heinrich became king Henrik III of Denmark. This lead to some trouble in Atlantis. The Hanseatic League also saw more internal competition: The cities in Holstein competed with the Dutch and Flemish cities, and the cities in the Baltic (and also those in OTL Hanover) stood aside a bit. After the Twenty-Year War, this would become even more apparent.
In 1435, the new king Gerhard was defeated by the Frisians under chief (yes, they had chiefs) Enno of the Cirksena family when he tried to conquer their lands.
A primitive kind of printing was developed in Antwerp 1442, which was center of cloth printing. It had no movable letters yet, but used wood blocks instead. Thanks to government contracts, the new technology soon spread through the Netherlands.
Colonies in the New World
Since ~1400, Europeans had taken up more or less regular trade contact with Atlantis. While they only imported tobacco first (which wasn't smoked ITTL first, but burned and inhaled instead, and mostly used as a medicine), the Europeans soon discovered the value of beaver and raccoon pelts. At the beginning, the trade was in the hands of the Hanseatic League, which helped the lords of Holstein-Holland-Hennegau to become pretty rich.
1438, The kings of Denmark and the Netherlands finally agreed for a compromise in the New World, negotiated by the pope: Denmark kept the northern colonies (Prince-Harald-Island, Haraldsland, New Jutland), which were extended with time over the whole OTL Canadian Maritimes and the Hudson valley. The Netherlands got the Southern colony of Nieuw Zeeland, which had been founded by the brothers Jan and Kees van Houten, and were allowed to colonize the lands further South. Since 1450, the Dutch sailed down the coast of Atlantis and founded settlements (i.e. trading places) in OTL Carolina, Georgia. Soon after, they were pushed aside by the stronger France; but on the other hand, they could conquer Anderland from Denmark in the anti-Danish War 1509-12. In 1543, they made a treaty with Florence, ruling the border between their colonies in Atlantis, and promising to respect them.
In 1531, Dutch founded colonies on OTL Guadeloupe, Dominica. And in 1543, with Scandinavia in Civil War / unrest, the Dutch (as other powers) used the opportunity and took Nystad, the capital of New Sweden.
1594, with Scandinavia in trouble, the Dutch used the opportunity and occupied Swedish Australia. But in 1600, the revolt of the "Söderlinger" (Scandinavians in Australia) against Dutch started, and in the "Australian War" 1615/16 Sweden defeated the Dutch, took back the colony.
Under the Wassenberg dynasty
1454, king Gerhard II of the Netherlands died without heir, so his lands fell to his old brother-in-arms Reinald of Geldern, who married Gerhard's daughter (although she was 30 years younger than him... but well, this is royalty) and also became king Reinald I of the HRE. During the Twenty-Year War, the Netherlands had to fight the French-Dutch War, which cost them a part of Flanders. Reinald II tried to challenge Karl V as Roman king, but couldn't succeed.
Since 1550, the trade of the Netherlands with Atlantis was painfully reduced; while they did most of the Atlantean trade before, even that of other nations, the Triple Monarchy of England-Castille-Portugal didn't need them anymore after the end of the Great Occidental War. An economical crisis broke out.
During the 1560s, the so-called Puritan movements started in the Netherlands. They were radically against any kind of luxury, especially in the church. Many were expelled too, had to go to the colonies in North Atlantis.
The French threat
After his death, his younger sons received small shares too (Namur and Frisia respectively). Namur seceded soon and was subsequently swallowed by France. And when the Triple Monarchy fell apart, the French danger became greater: 1630-35, France and Denmark-Braunschweig fought the Netherlands in the Anti-Dutch War. In the peace of Bremen, the Dutch chose to keep their Caribbean colonies, giving Denmark-Braunschweig Nieuw-Nederland instead. France got a good part of Flanders and all of Hennegau / Hainaut. As the Dutch said, now their Silver Age had also ended.
It was clear that things had to go on differently now. In 1638, reforms in the Netherlands after the lost war gave more power to the parliament, which was now democratically elected by all adult men who owned a house above a certain value.
The time after 1700 was considered the Bronze Age of the Netherlands. After the won war against France, the country could rebuild its former strength - although other powers, like Britain, France, Italy and Spain were now active in trade too. Fortunately, at least Sweden with its colony Australia (South Africa) and the Indian trade was Dutch-friendly.
After the death of king (and Holy Roman emperor) Eduard IV 1722, the Netherlands were united in personal union with Sweden-Norway-Mecklenburg. France objected the unification, found an ally in Luxemburg 1724; the Dutch War of Succession (also called Dutch War of Unification; first war in Europe since the end of the Great War) began. In 1729, it was resolved. France took Hainaut and parts of Flanders (again...), Luxemburg got Namur.
The Dutch also fought 1736-42 in the Palatinate War of Succession, to prevent France from gaining power.
The end as a state
The Dutch joined the French Republican Wars at the monarchist side, despite their developed democracy, for fear of France. But in the Battle of De Panne (March 1770), the French defeated the Dutch, who complained that the Brits didn't support them. In the Battle of Maasmechelen (April 1772), the last German-Dutch army was defeated.
The Netherlands stayed longer under French oppression than the rest of Germany. Even after the Rhenish War, most of them stayed occupied. However, France had to give Western and Eastern Frisia independence. Frisia became a part of Germany and a refugium for Dutch nationalists fleeing from the French.