No, I didn't write up an elaborate future history before designing Megacorps; rather, I added things as they occurred, mainly for gameplay reasons. But you can sort of reverse-engineer a future history from the game's elements.
From the country names, we can infer that, in the late 21st century, regional trade groupings are more important than the ostensibly sovereign nations that comprise them: NAFTA, the EU, ASEAN, and Mercosur are major powers.
Clearly the 21st century has not evolved in an entirely positive fashion for the United States, since most of the Islamic world is united in a Caliphate, and the existence of "Great Russia" implies that Russia has regained at least some of the territories lost at the implosion of the Soviet Union. Also, the euro has supplanted the dollar as the main global reserve currency.
Global warming appears to be under control, and one of the major industries is "solar". This does not seem to represent the manufacture of solar panels, however, since solar industries exist mainly in desert regions, rather than in industrial nations -- presumably, this reflects "active" solar generation of power, and we can imagine huge high-voltage lines under the Mediterranean, bringing power from the Sahara to Europe, and similar lines crossing North America from the Southwestern desert. The "drugs" industry is located not in places where large pharma exists today, but rather in places where cocaine and heroin are harvested -- a huge industry, evidently, although it's unclear whether it is now "legal," but if not, the Megacorps evidently don't pay much attention to what governments brand as illegal. Robotics, nanotech, and biotech are major industries in their own right, but oil remains important. The aerospace industry has made great strides since you can, in the course of the game, build an orbital colony at the L-5 point, and can also mine metals from the asteroid belt.
China is now the most militarily powerful nation on the planet, though NAFTA is nearly as strong; wars are fought more with Blackwater-style mercenaries than with national troops, however, and we can presume that these wars are short, sharp affairs between relatively small forces, rather than the wars of mass mobilization characteristic of the 20th century. If there are nuclear weapons about, evidently no one dares use them.
The most common systems of government are dictatorship, democracy, and kleptocracy ("rule by theft," a snarky but not unfair characterization of the government of, say, Russia today, and of Indonesia not long ago). Cards can change a country's system of government, but interestingly, there seems to be a one-way progression: Kleptocracies eventually become dictatorships, and dictatorships eventually become democracies. Of course, late 21st century democracy bears little resemblance to the liberal ideal; in an election, each media company has one vote. So much for the power of the people.
In a possibly hopeful sign, a new and somewhat mysterious political ideology is around, called "wikisyndicalism," and it appears that this is what democracies evolve into.
The world of Megacorps is clearly no utopia, and the increasing concentration of power in six gigantic conglomerates is worrisome; yet it has its positive aspects, too. Ecocatastrophe hasn't happened, nuclear war seems to be a thing of the past, technology continues to advance, and I imagine that most people live reasonably comfortable lives.