It split the world in two alliances: The English allies ( UK and Commonwealth nations, Spain etc.) and The Dutch allies (The Netherlands and Commonwealth nations, Germany, Austria, Belgium, Luxembourg etc.)
on February 20th 1921, The British had armed the border of South Australia. 311 thousand cannons were lined across the border. The northern Australian government asked the Netherlands to negotiate with the UK. But before they could, the south Australian army invaded the north, and a war began. On February 22nd the Dutch royal family got over to the UK to talk about the invasion, but the British guards captured them. Belgium began to fear the worst and called the Belgian army. Germany also noted the capture and responded with a letter. The letter said that if the royal family was not released, Germany would engage in war with the British. The government of the Netherlands also sent a letter that said the same thing as the German. The British responded with the murder of prince Hendrik. The Dutch got their fleets ready and attacked the British. Germany also sent their help.
Australian Anglo-Dutch war
on June 15th 1921 Australia, the south seemed to be winning, but Indonesia and New Zeeland reacted to the kidnapping and invasion of Northern Australia and began to send troops to Australia. In the battle of Oranjeburcht 3000 Dutch lost their lives and 4100 British, but it was an important turning point as Northern Australia had almost won back all of it's land. But south Australia had a back-up. They bombed five of the most important cities in northern Australia: Maasdorp, Alsmeer, Nieuw-Utrecht, Darwin and Carnij. This devastated the moral of the army. In September the southern army quickly swept the army away and occupied the north. New Zeeland seeing it's neighbor occupied, began to bomb southern cities. the south quickly followed by bombing New Zeeland's cities. New Zeeland gave in, but was already planning a plan with Indonesia to liberate them. Indonesia flew plane with aid to start the liberation.
Germany bombed London on July 8th 1921. The UK began to engage in naval warfare with the Dutch. But while this was going on, the British began to send troops to France. on August 25th, The British troops landed on French land. France was not prepared for war. While France tried to get the army together, the British had already occupied Brittany and both Normandies. Belgium also sent troops to France and the Netherlands. On September 30th 1921 German and Dutch troops landed on British land and the battle of the Isle of Wright the Dutch/German army quickly got past the British.
They quickly advanced to London and Buckingham palace. The British royal army fought hard but the some Dutch soldiers got past and entered Buckingham. George V was already waiting for the Dutch to arrive. he quickly entered on of the rooms and blockaded all the doors. Only the queen of the Netherlands and him.
Here he said. "Britain and her empire will not fall to you make-shift Germanics, this is the last time the British and the Dutch shall clash. I will not allow you to invade anymore land, this will end with British victory!" however Wilhemina grabbed a vase and smashed it on George's head. With George knocked unconscious, Wilhelmina quickly opened up the blockade and ran away. The Dutch quickly found her and escaped as soon as possible. Disguising herself as a normal English person, they made their way to shore.
After she made it to the Netherlands on September 35th, they started started a full offensive.
France however, had a hard time fighting the British, but with the Belgium help the French were able to keep them at bay.
The Americans also had their wars. starting on September 1921 with the invasion of Dutch America by Canada. Dutch america quickly fought back and invaded Canadian land. Louisiana also helped invading. On December 1921 the Spanish states of America began to worry, so they began to engage in warfare with Louisiana. Louisiana fighting two countries at a time, couldn't keep up and was invaded by both Canada and the SSA. Dutch America held back the Canadian but now also have the Louisianans to deal with. Both fought hard, but with the constant attacks, they seem to be losing. but they could keep up and held on.
In Europe February 1922, France was occupied by the British and Spanish (who recently joined after the SSA joined) Belgium quickly got their people to the Netherlands and Germany. But the British in France didn't go north, but south, invading Catalonia. Spain changed their plans and started counter attacking. Spain also sent letters to the SSA to tell them they need to let loose of their occupied area and begin to attack Canada. Spain fought with the British army until March 1923.
Occupied Australia was not bad, but people were forced to talk English and Dutch were insulted daily. The hiding Dutch also were deported to factories in the south. Children born in northern hospitals were also took from their parents and made British by be given to by British families. New Zeeland and Indonesia also planned attacks and had a full blown plan ready.
In America, the Dutch were fighting tons of wars, but after the Spanish let their occupied areas go and began attacking Canada, Canada began to lose. Louisiana was freed on June 1923. Canada was occupied by the Dutch, Spanish and Louisianans on December 12th 1923.
The Indonesian-Zeelandian plan was realized on April 8th and the Armies landed on Cape Oranje (OTL Cape Tork) and liberated North Australia. They occupied The south.
Britain, seeing all its territories occupied, gave in on July 1st, 1924
Britain was under Dutch and German control until 1925. After that they had their own government again but were supervised. South Australia was split in two, one occupied by New Zeeland an the other half occupied by North Australia.
Canada returned to being Canada in 1924.
British and Dutch relations were destroyed and the Dutch despised and mocked the British. Their relations didn't get better until the second world war, when both fought against the communist states.