[@BBlack Alice]Good questions :D

The Arkronains where able to assert its dominance over the continent due to a number of factors. I'll try to explain them here one by one.

1. The continent of Mycoria was never a united front. The different nations spend centuries warring eachother and where never able to to present a truely united front. The idea behind this roleplay is not player nations vs evil invader. The nations the players create could be favorable to the Arkronians, against them or something in between. During the rebellions some nations where against the Arkronians while others where on their side.

2. Superior mobility due to being technological advanced enough to cross the seas that are inpenetrable for the native nations. The Arkronians rule the waves and thus can ferry troops to other sides of the continent or sail up rivers to project power where it was neccisary. In short they have the best army and navy but are not like Nazi Germany that they just can walk in and oppress everyone who they please.

2. The Arkronians inplemented a system of indirect rule, much like how the Brittisch colonized India or how the Dutch seized control over present day Indonesia.. They worked together with local rules and made sure that being loyal to them was rewarding enough. In essence they managed the many conflicts on the continent and made sure that they where a game changer. Forcing the nations of Mycoria to more or less stop warring eachother. In short the Arkonians ensured that the local rulers could remain in power without being challanged by their neighbors, could use their power to aqcuiere wealth from within their own borders and do pretty much to their own population as they please.

3. Superior mobility due to being technological advanced enough to cross the seas that are inpenetrable for the native nations. The Arkronians rule the waves and thus can ferry troops to other sides of the continent or sail up rivers to project power where it was neccisary. In short they have the best army and navy but are not like Nazi Germany that they just can walk in and oppress everyone who they please.

The relations between the Arkronians and other states could best be described as vassal or tributary states. The states are bound to serve the Arkronian crown by a series of treaties but apart from that are mostly independent. They have their own governments who rule their respective lands, their own distinct cultures and societies and can make most decicions independtly from the Arkronian crown. However the Arkronians ofcourse have implemented certain instruments to assure their dominance.

1. All states must pay tributes. There are certain forms of taxation to all states that are designed to benefit the Arkronian crown while limiting the capabilities of states to grow much stronger and challenge their rule. The tributes could be money, resources, manpower or something different.

2. Foreign policy must be conducted in conjuction with the Arkronian crown. For centuries if nations want to make agreements with eachother they had to meet in the Arkronian capital and do the negotiation in front of Arkronian officials. All formal agreements had to be accepted by the Arkronian crown. Ofcourse there where still informal agreements and secret meetings.

3. The Arkronains are allowed to settle in all lands and have military access to all nations. They will have offices, spies and traders in most nations. They could also have some form of military presence. That presence does not neccicarily have to be native Arkronian soldiers. That could also be regiments formed from soldiers from other nations. Just like the roman auxiliary system. 

4. The Arkronians have banned the development of shipbuilding technology throughout the continent and monopolized it for their own kingdom. This is to ensure that they remain the dominant naval and trading force on the continent.

Ofcourse this sounds a little bit restricting. However as you have have proberbly read, the Arkronian system is on the verge of collapse due to a mysterious decease ravaging through their race. In essence they are a dwingling power and the nations wich the players will create are pretty much challenged by the question of how to shape their future in a post-Arkronian rule Mycoria. The Arkronians are still around, are still powerful but their dominance is dwingling. What is written above is the starting point but can be redefined throughout the roleplay.


Now to the subject of religion:

Religion is the way how the cultures and people describe the forces of the universe. It is both mythical and very real. I can be a source of great influence, power and magic. It can be used the explain what we don't understand and unify people under a common cause. The players are free to create their own religions. Religion might produce miracles but mostly it will be shrouded in mistery if it was truly the influence of gods, spirits dieties, a lucky chance in circumstances or outright trickery. A way to handle it could be something like this. 

"during a great drought the priest called upon the people for human sacrifice. Every night the priests sacrificed 10 lives to the gods and on the 1oth night the rain finely came" 

Where the gods finely pleased enough when the 100th soul entered the afterlive or was it just a matter of preseference until the weather changed? Some of the people might argue for the latter while others considered themselfs saved by the gods. 

I hope this answers your questions a bit :)