In ITL 110:
A popular place to visit, Orikodisata was well-known as an appealing destination, and would probably rival Seijaces for the most densely populated city in the world if the government were more lenient on immigration.
Seems like people visit Orina Anoris, traveling and vacationing, but it's hard to get in and stay as a citizen. We know that Jacacea, on the other hand, is happy to assimilate new people into the population.
You bring up good candidates when you mention merchants and refugees. I'd imagine that marriage might be the easiest way in. (Not sure how "easy" it would be, though, because if the marriage has to be recognized by the Anorian government, you'll need official blessings, so a quickie green-card type marriage wouldn't work too well.)
(The above is all speculation, not canon.)