Arial Policy II

It is very idiot move to levied taxes onto a kingdom that could barely feeds itself.

Only after the chaos subsided, the markets could be opened and merchants could move around that the economy could breathe again

In the Empire for example, after Arial had finished his vengeance against Zettel, he had begun exempting them from taxes for a few years.

But while Zettel were exempted from taxes, this did not mean everything was exempted. After all, if that kingdom did not produce anything for the Empire what use does it have?

And it is not like Arial did not gain many golds when he was sacking the cities and capital of Zettel

It is only after all of these kingdoms is stable that Arial could maintain a fixed rate of taxation for every kingdom under the Empire

He wanted to make it uniform. 

As for the state of Balhae, he first wanted to maintained existing levels of taxation. That was his original plans.