I'm running into a small issue with my environment, the setting is about a thousand years in the future. The story revolves around several geopolitical & environmental issues. So far, except for a world government (acting only on issues affecting the planet as a whole) I've left the individual countries intact. I need to be able to refer to different countries all over the world. The major realism issue I've run into is that the chance of current countries surviving with the same names for a thousand years seems unrealistic to me. However, since there is a lot of religious & racial conflict happening also I don't want to use made up names of countries because the reader would have trouble linking country Blahblah as a Muslim region or that Whateverstan is an isolated island country (like Australia) and while racially & religiously mixed it contains it's own unique culture. Can I get away with this somewhat small plot hole?
Just off the top of my head, I'd say probably not. Think BACK 1000 years to the year c.1016. Look at maps, etc. How different was the world then, from now? And keep in mind things changed more slowly then as well. If I were you, I'd resign myself to changing countries, names, etc. Not all of them, but enough of them to be believable. Some countries will join with other countries to form new ones. Some will be conquered and renamed. Some will split off and become two countries. Religions may change as well. I wouldn't assume a static world if you want it to be believable.
Generally I'm in agreement with @jannert - BUT you might be able to get away with it if you establish it properly. So you say there's one single global government. Fair enough, but presumably it would have subdivisions for administrative purposes (and this might involve some kind of federal power-splitting too) - but the names of those subdivisions might still be based on (roughly) the modern countries' names. Think about it; if you've got an administrative area that covers modern-day China, what else are you going to call it other than China? (You might split something that large into East-China and West China, mind.) As long as you establish that the regions are named after their "traditional" names, you should be fine. (Oh, and don't be too US-centric with it - you're not going to have a region called "the mid-west", on the basis that that name only makes sense if you're already making the assumption that you're talking about the US.)
Here's a horrible thought. Maybe one country has conquered the entire planet. The whole world is now called North Korea.
That's sort of how I started thinking of this hole. I referred to the Middle-East and then later realized that term alone might be an issue for a civilization a thousand years from now.
It's already a reasonably problematic one, eurocentric as it is. Depending on where you're referring to, "Persia" might be a suitable replacement. People have a rough idea of where it refers to, but it doesn't map exactly onto any modern country (though it's usually used to mean "Iran").
Go with the European Union concept. Australia and the Pacific islands might be banded together as Pan Oceana. The North/South Americas might just be the American Trade Bloc. That sort of thing. Much easier to have just a handful of regional players as opposed to lots of individual nations.
Ten years in the future, in an effort to achieve world peace, the UN writes and forces all countries to sign the "Ethnohistorical Preservation Act", forbidding the shifting or removal of country borders. Kind of dramatic, but something you can play with.
Well... that works, providing you want to portray the UN as a tyrannical antidemocratic power. I didn't really get that impression from the OP.
First off, don't call Australia an island, you don't want those Aussies mad at you. Possibly you can use the continents naming and simply subdivide it as needed, The American continents already have some subdivision along these lines such as north, south and central, and divvying up the Eastern world such East Europe, West Europe, North Europe, Mediterranean Europe, and so on for as much division as you want. The names of continents should be stable even for a thousand years depending on what transpired during all that time.
Some countries have been alive for over 1,000 years, Just saying. At heart, this is a moot issue to me. Because if someone doesn't like your story because of this detail. Well, that person is never going to be pleased. What you call the nations is a seriously minor issue. And there is cause to assume names did survive. But I hold on the other point more. That if people are upset with what you call places, or not calling them something different, they are nit picking. Ideas like this you get to focus on as much or as little as you want. If you don't bring up logical reasons for names to be different, I am not going to wonder why China in year 3017 is still China. Even if there are some logical reasons, I can understand that this is for my benefit, much like how a Japanese movie can be tranlated to English with subtitles. Them speaking English in Tokyo really makes no sense and they went to effort to make this change, but the change was so that I didn't have to read every line. I get that. Even if I don't mind subtles, I get the creative reason and as such am not going to be angry at it.
Thanks for all your thoughts The Universe is definitely being shown as a democracy at the level of World Government with each region having representatives sent to a World Senate. However, the regions are grouped up so that individual countries are pushed together based on populations. There's a region called the US region but it includes Canada, USA, Mexico and some of what's left of Central American countries. Then there's a North African region that has Northern African countries along with most of the Mid-East Then Europe, Asia, are their own regions Australia, New Zealand, and South America are underwater and gone. (Post polar cap melt so the rest of the world has plenty of flooded areas) While I'm implying that each individual country still governs their own areas I'm not going into because it's not a necessary part of the story.
For what it's worth, it seems more logical to call this America. I suspect that Canada, Mexico, etc., wouldn't be delighted to be submerged under the United States, while there would be pretty much universal agreement that the continents involved are North America and South America. I think.
I would bet first that the modern subdivision into continents and regions would probably survive... Europe, Asia and Africa are names that are already more than 2000 years old. The Americas and Australia will probably survive as continent names, the Middle East as a region. Africa as a region is always divided in two: North Africa and sub-Saharan African are distinctively ethnically , culturally and linguistically separate, so those regions will subdivide and follow different paths. What powerful states will endure the next thousand years depends on what happens. Since the UN and world government still exist in your story, this implies nothing catastrophic happened: no global economic collapse, no global nuclear war that annihilated chunks of the planet, no global pandemic, nothing to wipe out all knowledge and institutions. Your setting does not appear to be post-apocalyptic. So the countries that would fragment would be those that seem likely to fragment now. Not interested in starting a political argument here, but I see internal stresses in the US and the EU that could cause those two giants to break up into smaller, potentially hostile chunks, likewise Russia, which might divide east and west, Muslim and Christian, happening over the next hundred years. China could go either way. It has been around for 5000 years but its history is one of cycles of collapse into warlord statelets, followed by re-accretion and resurgence to long periods of stability, with about a 500 year period. It just started such a period of resurgence, so I bet it will be around a while. Along with disintegration there is potential for new power blocs to emerge. South America is one, especially if the giant to their north disintegrated. Los Estados Unidos del Sud? Parts of southern Africa could integrate from tiny entities to a regional bloc. Lots of resources there, but it might not happen peacefully. South Africa appears to be the country with the education, economy and military power to enforce a southern unification. Islam is in crisis today, not unlike Christianity after the fall of Rome. In the past, when it has been in an upswing, it was a powerfully unifying force, both inspirationally and militarily. The golden age of Islam a thousand years ago saw Baghdad as the Athens of the Middle East, where algebra was invented, and center of a global Caliphate from Spain to the Philippines. If the right side wins the struggle for the soul of that religion, you could see that happen again. Alternatively, if the wrong side wins, you could see the region go into a death spiral of disunity. And a thousand years ago, Europe was more like Afghanistan ten years ago! Bottom line, project the trends you see today, to their logical (or a logical) conclusion, and you will not have a plausibility issue. Those that break up will need new names, those that coalesce will also need new names, my bet that those that did not change much will have the same name.