Where some of those characters actually US citizens and not foreigners. Not sure, just sayin though.
Good question. Let me consult the "Lostpedia".
(a couple of deft Google searches later)Sun (
Yunjin Kim) and her husband Jin (
Daniel Dae-Kim) were South Koreans. However, these actors have subsequently both portrayed Americans, in ABC's
Mistresses and in CBS'
Hawaii 5-0 respectively.
Eko, also known as Mr. Eko and Father Tunde (
Adewale Akinnuoye-Agbaje) was Nigerian. He has played Americans in films such as
Suicide Squad and
Concussion, both alongside
Will Smith. The irony is that in the latter film, a biopic,
Will played the Nigerian doctor Bennet Omalu with such a terrible attempt at a Nigerian accent that a comedian joked that
"Will Smith played a Nigerian, but one with a concussion." Sayid (
Naveen Andrews) was Iraqi, but
Naveen has played Americans in such films as
Planet Terror.
Claire (
Emilie de Ravin) was Australian, but
Emilie has played Americans on TV shows like
CSI: Miami and
NCIS, and in films such as the remake of
Stephen King's
Carrie.
Kate (
Evangeline Lilly) was American, from Iowa.
Charlie (
Dominic Monaghan) was English, but
Dominic has played Americans in films like
X-Men Origins: Wolverine and on TV shows like NBC's
Chuck.