Dwilight was the roleplaying island.
That is incorrect.
The Far East was the RP-heavy island; however, that was never properly defined or consistently enforced.
Dwilight is the island of Serious Medieval Atmosphere. This has always been much more clearly defined, and is much less strict than the FEI's. It means that characters are expected to act like they are a) real people, b) nobles, c) in a medieval setting.
Nowadays, this requires much less of a change in mindset compared to the rest of the game, because much of what makes it up spread to the other continents after Dwilight was opened; however, previously, there was a
lot more casual use of modernisms, silly behaviour, and other blatant violations of Serious Medieval Atmosphere.
