And I thought you called them barbarians 
Seriously? That’s an actual ethnic group! Is there some kind of anti-Vlach sentiment in Greece? (AFAIK, I’ve never met a Vlach. But there are Vlach communities in Bulgaria and I knew someone that lived in a Vlach village, an absolute shithole on the Serbian border.)
In Hindi we say “pendu” - someone right out of the village, basically.
In these parts we usually use common American English terms like hicks and rubes. “Redneck” is less common, having a political connotation. However, a particularly lovely local term, of which I am very fond, is “Dirt.” Not in a collective sense, but singular and plural; “The guy she brought home was a dirt” or “Two dirts came into the store.” Great word.
Japanese:
These might be old fashioned. Until recently I lived in a rural area, so the people I knew were those who would be insulted, not those making the insults.
田舎っぺ inaka’pe. The first part, inaka, means countryside, rural. The 'pe ending is emulating a rural accent. Kind of like poking fun of people who live in southern states by doing a bad imitation of their accent: “jaworja” instead of Georgia or “looziana” instead of Louisiana.
いも imo, lit.: potato
A lot of people have a 方言 hôgen, regional dialect, particularly people from outside the Kanto area. Mocking the way someone speaks is a common way to insult someone with a strong regional accent. There are probably also a lot of area-specific slang terms that I wouldn’t know.
I’ve always liked “scrote,” short for scrotum, since I heard a rural cop use it to refer to a redneck: “Billy Bob is just a dumb, lazyass scrote.”
In my reading on Cold War Russia, I remember nekulturny being used as a putdown - “uncultured.” Not sure if it still has that connotation.
Usage may vary, but for me, a stubblejumper just means someone from the rural parts of the prairie provinces, or even just from the prairies generally, including the cities. I don’t think it has the connotations that redneck has. I wouldn’t mind being called a ‘stubblejumper’, but I’d be bothered by being called a redneck.
In Spain you can say that someone is “de pueblo”, but that in and on itself only means they’re from a small place. What can make being “de pueblo” or “de ciudad” derogatory is the tone employed and perhaps additional gestures.
In both cases, if you’re using the expressions derogatorily, one of the things you’re saying is that this person can’t find his mouth while eating if he happens to be out of his usual fishbowl. For example, when my mother (born in Barcelona) can’t remember that you’re supposed to stand the right on escalators, I ask her “what, we’re de pueblo, eh?” (no escalators in the town where she now lives); when my Barcelona cousin came to spend Fiestas here many summers ago, and on one hand she complained about the lack of public transportation (“but I’m tired!”) and on the other about the place being too small (“haven’t we been here already?”), my exasperated friends finally told her “you’re de ciudad, ain’t you? Well, we’re not! You can shut up or shut up.”
Maybe there was anti-Vlach sentiment in the distant past, nowadays most Greek people are not even aware that Vlachs are an ethnic group, they simply think the word means “redneck”.
By the way Vlach (ΒΛΑΧΟΣ) is a rather common Greek surname. Maybe the people who carry that surname are descendants of Vlach people.
In the UK it tends to be “yokel” or “Farmer Giles”.
Although that’s more for “honest rural folk who like tractors and not flash city ways” - i.e. patronising but affectionate.
“Redneck” in the derogatory sense of “pickup trucks, bad hair and wife-beating” would either be “pikey” or “chav” I guess.
“Nekulturny” is a reasonably nasty insult in Russian, but it predates the Cold War and would still be considered very rude today. It literally means “uncultured” but it’s not precisely equivalent to rube, hick, etc. You’d apply it to someone who was crude or ill-mannered, not necessarily a hillbilly type. It’s more “Rude asshole” than “redneck.”
In Cuba they use “guajiro”.
I guess people use “redneck” now the way they used to use “hillbilly.” I’m more comfortable with the latter.
The general Arabic word is bedu, which means bedouin or desert nomad folk, and just like in English, there are people who are proud to call themselves bedu, and there are also a lot of regional variations. My understanding is that within Saudi Arabia, people from al-Hassa, or Hasawis, are the hillbillies.
Yes, but that’s akin to farmer. Since the OP asked for equivalent or “redneck, hick, cracker, white trash, trailer park people” the correct answers would be:
seboruco (rock, as in rocks for brains), boniato , ñame (both root vegetables), again having these instead of brains.
Of course these insults are used when talking about guajiros, never when talking TO guajiros. Most guajiros tend to carry a machete.
No… we call 'em Tasmanians 
Only Kidding
In Puerto Rico, jíbaro is the name given to the farmers/rural people. It can be used unoffensively, offensively, and as a compliment, depending on the person. As an insult, though, it is kind of mild, sort of naïve/gullible/uneducated or shy/wary instead of willfully ignorant. I’ve been called jíbara due to my shyness by relatives.
More insulting is being called cafre… it is a term used more for something or someone that is one or more of the following: vulgar, low class, bad dialect, little manners, poor taste, some fashion tastes. Anything considered the lowest category, basically. Keep in mind that this does not need to correlate with socioeconomic status.
Interesting! Growing up in WV, we called the kids from up the holler “grits.” It could also be an adjective. The Appalachian Literature class at my high school was known as Grit Lit.
“Grit” meant dirt, not the hominy dish of the south. I’ve never encountered this usage since leaving WV.
When my dad was in Southern Africa in the 1970s the Afrikaans term redneck (Rooinek) was a derogatory term for Englishman.
To be honest I’d be suprised if there was a single major language without a term for “Country-dwelling uncouth simpleton”. Its a basic social division in human civilization between the “sophisticated” city-dweller and their “less sophisticated” country-dwelling cousins. In fact the very term “civilization” itself implies such a division (that if you don’t live in a city you are an “uncivilized” redneck).
I’d come awfully close to suggesting “naco” for Mexico. My wife is a real Mexican, and she’s never satisfactorily supplied a good, equivalent expression. Heck, I think I’ve got her using “cuello rojo” and “basura blanca” these days.
“Campesino” isn’t used as “redneck,” but it can be used both neutrally and derogatorily. If someone does something that’s not socially acceptable, for example, he’ll be excused for it, because after all, he’s just some stupid campesino.
Also as Nava says, I sometimes hear "de(l) pueblo"used in similar contexts as in Spain.
Instead of “del pueblo”, in Puerto Rico they use “de la isla” vs “del (área) Metro” to distinguish those that are from the municipalities outside of the San Juan Metropolitan Area.
But it is not by itself a derogatory term, just a location.