Nit-pick: it’s C. Thomas Howell, actually.
Scottish, not Welsh. And just to pick nits, Captain Ramius was Lithuanian, not Russian.
Sam Neill’s character, on the other hand, was indeed Russian. 
The Costanza family on Seinfeld was not even a LITTLE bit convincing as Italians. Every actor who played a Costanza fit every imaginable Jewish stereotype!
I will confirm that, here in Texas at least, it’s not at all uncommon to hear Indians, Chinese, Koreans, Pakistanis and Vietnamese who have noticeable drawls, and who use expressions like “y’all” without any self-consciousness.
Heh! Reminds me of when I was teaching English in Moscow. The language school where I worked had a branch in one of the suburbs where a certain teacher from Ireland had been assigned for years. When he finally decided to move on, the teacher who replaced him found that all of the students (teenagers) spoke English with a perfect Irish accent.
Like little kids, whose brains soak languages up like sponges, immigrants who learn English through immersion end up speaking it with the accent they hear.
I’ll mention this anecdote again. I knew an Algerian girl who spoke French and English. Arabic was her first language. Then French, and then English. Her English was absolutely flawless and fluent–but with a definite French accent!
Did she learn English through immersion? If she learned it in an Algerian school, it’s very possible her instructor taught it with a French accent, since Algeria was a French colony until about 50 years ago.
Or her French accent might have been so deeply ingrained that she kept it regardless of where her instructor was from. But I’ll bet she did indeed learn it through formal instruction, and not immersion.
I knew a Russian girl who shacked up with a Scot. After six months, she sounded like she’d just walked in off the streets of Edinburgh.
Don’t even get me started on Donna Chang…
And then a pasty white Englishman
Never axed her, but this was my assumption, that her teacher’s first language was probably French, and was teaching English.
You’re right, none of those guys are from Belfast!
My own feeble defense of ‘Khan’/ a certain set of pecs/ #2’s impeccable posture… has two prongs:
1)Surnames aren’t an infallible guide to a person’s cultural lineage. Adoptions, legal name changes, immigrants to who change their name to a more ‘local’ version of their name to avoid stigma, the many Scottish surnames in the Caribbean which are mostly to do with Slave and Plantation ownership, religious conversions, the fact that in the West (most) cultures hand down surnames via the father’s lineage. That might only be 1/200 or less of your ‘ethnic’ background (which is, itself, a hot potato to define…)
2)Not all Sikhs are turban wearing Punjabi’s. You can convert to Sikhism like this Italian-American taxi driver:
From Scotland (where I am),we’ve 2 media personalities and brothers, who are both Sikh- Hardeep Singh Kholi, a comedian and presenter, wears a Turban- at times with a kilt (and looks dapper with it). And Sanjeev Kohli, an actor and presenter, who doesn’t wear a Turban, and is perhaps best known playing bearded Muslim shopkeeper, Navid, in ‘Still Game’-a sitcom.
It was made pretty clear in ST: TOS that Khan was originally envisioned as coming from northern India, whose men “make the most magnificent warriors!” (Marla McGivers’ words, not mine.)
http://www.racebending.com/v4/wp-content/uploads/2013/05/startrek02.jpg
A Japanese-American friend of mine once mentioned that he was kind of annoyed that the character named Mr. Kobayashi in The Usual Suspects was played by Pete Postlethwaite. My friend is biracial himself and has a Japanese last name even though his mother is white, so he wouldn’t have been surprised by a multiracial actor having a Japanese name, but he felt Postlethwaite was obviously a white guy with zero Japanese ancestry.
I agree that Postlethwaite didn’t look the least bit Japanese, but the end of the movie reveals that there’s a good reason for this white man to have a Japanese name. I’m going to spoiler box this reason because The Usual Suspects is a movie with some major plot twists and it’s impossible to talk about the ending without giving some of them away, but I’ll try not to give away more than necessary. “Kobayashi” was a fake name invented by Verbal Kint (Kevin Spacey) to throw off the police. It’s shown that the Kint drew inspiration for some of the names and details in his story from objects in the room with him. For instance, there’s a mug marked “Kobayashi Chinaware”. The “Mr. Kobayashi” in his story was based on a real (in the movie) person also played by Postlethwaite, so during the flashback/story scenes he’s shown as Postlethwaite rather than an Asian actor.