The Arcadian Union (or sometimes referred to as just Arcadia) is a formable nation that is in the continent of Arcadia, where it gets its name from, and either Plantagenia, Vinland, or The Belgian Confederacy can form the Union. Typically it will border Qingqiu, Venice/Athesia, Lusitania/Gran Colombia and even Japan.
Overview[]
The Arcadian Union is easily one of the most powerful nations when it's formed, as it gives you cores over all the rich and populous lands of Arcadia. You'll have lots of coal and iron, as well as oil later on in game if you manage to take your cores back from Gran Colombia or Lusitania, depending on how the Congress of Andagoya turns out. Your army can easily become the biggest in the world, along with a massive navy too, of which you should be able to fund sufficiently with the massive amounts of money you'll rake in, both from your industry and exports.
As the Arcadian Union, you have several options to expand your great nation. Most notably, the expansion into the Rocky Mountains via decision, which will give you cores on much of Qingqiu's land, pushing them back further to the coastline. Unfortunately, you won't be able to accept Qinqiuan pops, but they will quickly assimilate to your primary culture. You also have a choice to gain Athesia from Venice. You can attempt to go for the Andagoya Canal, expanding your influence over the Caribbean and giving you access to Ameriga if you either want to sphere them, or expand there.
Via decisions, you can get several more accepted pops. You can add Afro-Frankish, Afro-Germanic and Afro-Italian (if you bought Athesia) cultures, along with several native cultures, which are done through decisions.
You can also colonise Africa if you choose to. Because you have a large number of ports on your cores - which increases your colonial power - you should be able to contest any other nation colonising Africa. But, unfortunately, you won't be able to reap the benefits of the 'Scramble for Africa' CB, as only nations with their capital in Europe are able to gain access to this powerful CB. You can also attempt to annex Qingqiu and take Kita Kaigan from the Japanese, if you want to dominate both sides of the continent. If you manage to sphere nations like San Salvador, Andagoya or any other South Arcadian nation, you can form a puppet there, with control over most of OTL Central America. You can also opt to puppet whichever other nations may remain on Arcadia, for total dominance over the continent. Alternatively, you can try to kick the Europeans out of the Caribbean, releasing the Spanish, Scandinavian, Burgundian and Couronian colonies.
Forming The Arcadian Union[]
The Arcadian Union isn't too difficult to form; it's a fun initial campaign to form the Arcadian Union, and in the end you're left with an immensely powerful nation that's in the perfect position to become the dominant power of the world.
The Belgian Confederacy[]
The Arcadian Union with all its cores and some colonisable land.
As the Belgian Confederacy, you should go on the offensive very early on, mainly attacking Plantagenia and Vinland for states so you have the advantage in future wars. Whichever one of the two is weaker at the start and with the least amount of allies is the one you should attack first. This usually is Vinland, who can become harder to fight afterwards as they tend to like allying Gran Colombia if they don't fall apart. Following this, you should attack Plantagenia to take back your cores there too.
After these initial wars, make sure that you've secured yourself as a Great Power (GP). This can be done by building up an industry - which isn't too difficult as you have a lot of good RGOs like coal and iron - or by prestige spamming. Whilst you wait to become a GP, improve relations with Vinland and Plantagenia. You should also be influencing them once your truce with them has expired.
After a while, you will be able to add them both to your sphere, and once you have, the decision to form the Arcadian Union should be unlocked!
Plantagenia[]
As the Plantagenets, you have a more diplomatic approach to forming the Arcadian Union, to say the least. You will usually find yourself at war or otherwise at odds with the aggressive Belgian Confederacy at the start, so you should begin by playing defensively in the Appalachian mountains against the large and well-equipped armies of the Septimans. After a few defensive mountain battles with a reinforced army waiting on the other side of the mountains, you should have won the war against the Septimans. During the peace deal, the player should retake their cores from the Belgian Confederacy, which should then spur Vinland to do the same, leaving the Septimans with a tiny rump state.
You should also start colonizing the great plains while you're a secondary power. After that, start trying to expand into Vinland after to get your cores on OTL Michigan. Avoid colonising any land that Qingqiu has cores on, as they will attack you later on when you might be preoccupied in another war. You can get cores on this land later anyway.
Vinland[]
Vinland is the most difficult of the three options, primarily due to its low population at the start of the game. As Vinland, you should wait and hope for the Belgian Confederacy to attack Plantagenia, and then attack the Septimans as they're occupied with Plantagenia. You should aim to take back all your cores in the north, and maybe even some more just to make use of that early-game infamy reduction.
Make sure that you have built up a decent army too, of about 1-2 30K stacks once you are done with the war. It's likely that the unhappy Septimans might try to join back with their homeland. Rebels aren't too hard to squash anyway, so this is unlikely to pose as a huge challenge to you.
Begin to improve relations with Plantagenia, even if you have cores on them. Once you become a GP, you'll have to sphere them, and conquering them will take far too much time and infamy. Whilst you do this, make sure that as you continue to beat up the Septimans, you return their cores to Plantagenia too. Once you can, puppet the now puny Septiman state. This should allow you to form the Arcadian Union, provided that you have already sphered Plantagenia.