only Osama knows
Afghan
IRANIAN is the appropriate national descriptor. However, many Iranians prefer to be called Persians, especially if they live outside of Iran and do not identify with the current regime.
No, it is the adjective derived from the word Afghanistan as in "an afghan rug".
The proper adjective for southwest is "southwestern."
The proper adjective is Haitian.
The proper adjective for Portuguese is "Portuguese."
Vietnamese is the proper adjective for Vietnam.
The proper adjective for George is Georgian.
The proper adjective for Siam is Siamese.
Mayan is itself a proper adjective.
Freudian is the proper adjective for Freud.
The proper adjective for Georgia is Georgian.